Program

Q1. Program to input values into an array and display times.

 #include <iostream>  
 using namespace std;  
 int main() {  
   int arr[4], i;  
   cout << "Enter four elements of an array: ";  
   for(i = 0; i < 4; i++) {  
     cin >> arr[i];  
   }  
   cout << "The elements of array are: ";  
   for(i = 0; i < 4; i++) {  
     cout << arr[i] << " ";  
   }  
 }  

Q2. Program to find the largest and smallest number in the array.

 #include <iostream>  
 using namespace std;  
 int main() {
    int smallest, largest, i, temp = 0, arr[10] = {2, 5, 6, 7, 1, -3, 15, 0, -5, -9};
    smallest = largest = arr[0];
    for(i = 0; i < 10; i++) {
        if(arr[i] > largest)
            largest = arr[i];
        
        if(arr[i] < smallest)
            smallest = arr[i];
    }
    cout << "largest number: " << largest << "\n" << "smallest number: " << smallest;
    return 0;
 }

OUTPUT:

 largest number: 15  
 smallest number: -9  

Q4. Program to reverse the elements of an array.

 #include <iostream>  
 using namespace std;  
 int main() {  
      int start, end, temp = 0, i, j , arr[5] = {2, 5, 3, 1, 9};  
      start = arr[0];  
      end = arr[4];  
      for( i = 0, j = 4; i < j; i++, j-- ) {  
           temp = arr[j];  
           arr[j] = arr[i];  
           arr[i] = temp;  
           start = arr[i];  
        end = arr[j];  
      }  
   for(i = 0; i < 5; i++)   
     cout << arr[i] << " ";  
 }  

OUTPUT:

 9 1 3 5 2

Q5. Program to pass array elements to a function.

 #include <iostream>  
 using namespace std;  
 void check(int num);  
 int main() {  
   int arr[5];  
   for(int i = 0; i < 5; i++) {  
     cin >> arr[i];  
     check(arr[i]);  
   }  
 }  
 void check(int num) {  
   if(num%2 == 0)  
     cout << num << " is even number" << endl;  
   else   
     cout << num << " is odd number" << endl;  
 }  

INPUT:

 5 7 0 4 6

OUTPUT:

 5 is odd number
 7 is odd number
 0 is even number
 4 is even number
 6 is even number

Q6. Program to pass an array to a function.

 #include <iostream>  
 using namespace std;  
 void func(int val[]);  
 int main() {  
   int arr[5] = {1,2,3,4,5};  
     func(arr);  
   cout << "Contents of array are now : ";  
   for( int i = 0; i < 5; i++)   
     cout << arr[i] << " ";  
 }  
 void func(int val[]) {  
   int sum = 0;  
   for(int i = 0; i < 5; i++) {  
     val[i] = val[i] * val[i];  
     sum += val[i];  
   }  
   cout << "The sum of squares = " << sum << endl;;  
 }  

OUTPUT:

 The sum of squares = 55
 Contents of array are now : 1 4 9 16 25 

Q7. Program to input and display matrix.

 #include <iostream>  
 #define ROW 3  
 #define COL 4  
 using namespace std;  
 int main() {  
   int mat[ROW][COL];  
   cout << "Enter the element of the matrix [3][4]: \n";  
   for(int i = 0; i < ROW; i++) {  
     for(int j = 0; j < COL; j++) {  
       cin >> mat[i][j];  
     }  
   }  
   cout << "The matrix that you have entered is: \n";  
   for(int i = 0; i < ROW; i++) {  
     for(int j = 0; j < COL; j++) {  
       cout << mat[i][j] << " ";  
     }  
     cout << "\n";  
   }  
 }  

INPUT:

 Enter the element of the matrix [3][4]:                        
 1 2 3 4                                        
 5 6 7 8                                        
 9 0 1 2   

OUTPUT:

 The matrix that you have entered is:                       
 1 2 3 4                                        
 5 6 7 8                                        
 9 0 1 2   

Q8. Program for the addition of two matrices.

 #include <iostream>  
 #define ROW 3  
 #define COL 4  
 using namespace std;  
 int main() {  
   int mat1[ROW][COL], mat2[ROW][COL], mat3[ROW][COL], i, j;  
   cout << "Enter the element of the matrix [3][4]: \n";  
   for(i = 0; i < ROW; i++) {  
     for(j = 0; j < COL; j++) {  
       cin >> mat1[i][j];  
     }  
   }  
   cout << "Enter the element of 2nd matrix [3][4]: \n";  
   for(i = 0; i < ROW; i++) {  
     for(j = 0; j < COL; j++) {  
       cin >> mat2[i][j];  
     }  
   }  
   /* Addition */  
   for(i = 0; i < ROW; i++) {  
     for(j = 0; j < COL; j++) {  
       mat3[i][j] = mat1[i][j] + mat2[i][j];  
     }  
   }  
   cout << "The matrix that you have entered is: \n";  
   for(i = 0; i < ROW; i++) {  
     for(j = 0; j < COL; j++) {  
       cout << mat3[i][j] << " ";  
     }  
     cout << endl;  
   }  
 }  

INPUT:

 Enter the element of the matrix [3][4]:                                             
 1 2 3 4                                                                             
 5 6 7 8                                                                             
 9 0 1 2                                                                             
 Enter the element of 2nd matrix [3][4]:                                             
 2 1 0 9                                                                             
 8 7 6 5                                                                             
 4 3 2 1

OUTPUT:

 The matrix that you have entered is:                                              
 3 3 3 13                                                                          
 13 13 13 13                                                                       
 13 3 3 3

Q9. Program for multiplication of two matrices.

 #include <iostream>  
 #define ROW1 3  
 #define COL1 4  
 #define ROW2 COL1  
 #define COL2 2  
 using namespace std;  
 int main() {  
   int mat1[ROW1][COL1], mat2[ROW2][COL2], mat3[ROW1][COL2], i, j;  
   cout << "Enter the element of the matrix [3][4]: \n";  
   for(i = 0; i < ROW1; i++) {  
     for(j = 0; j < COL1; j++) {  
       cin >> mat1[i][j];  
     }  
   }  
   cout << "Enter the element of 2nd matrix [4][2]: \n";  
   for(i = 0; i < ROW2; i++) {  
     for(j = 0; j < COL2; j++) {  
       cin >> mat2[i][j];  
     }  
   }  
   /* Addition */  
   for(i = 0; i < ROW1; i++) {  
     for(j = 0; j < COL2; j++) {  
       mat3[i][j] = mat1[i][j] * mat2[i][j];  
     }  
   }  
   cout << "The matrix that you have entered is: \n";  
   for(i = 0; i < ROW1; i++) {  
     for(j = 0; j < COL2; j++) {  
       cout << mat3[i][j] << " ";  
     }  
     cout << endl;  
   }  
 }  

INPUT:

 Enter the element of the matrix [3][4]:                         
 1 2 3 4                                         
 5 6 7 8                                         
 8 9 1 2                                         
 Enter the element of 2nd matrix [4][2]:                         
 1 2                                           
 3 4                                           
 5 6                                           
 7 8                                           

OUTPUT:

 The matrix that you have entered is:
 1 4 
 15 24
 40 54 

-:POINTERS:- 

Q1. Program to dereference pointer variables.

 #include <iostream>  
 using namespace std;  
 int main() {  
   int a = 87;  
   float b = 4.5;  
   int *p1 = &a;  
   float *p2 = &b;  
   printf("Value of p1 = Address of a = %p\n", p1);  
   printf("Value of p2 = Address of b = %p\n", p2);  
   printf("Address of p1 = %p\n", &p1);  
   printf("Address of p2 = %p\n", &p2);  
   printf("Value of a = %d %d %d\n", a, *p1, *(&a));  
   printf("Value of b = %f %f %f\n", b, *p2, *(&b));  
 }  

OUTPUT:

 Value of p1 = Address of a = 0x7ffe34a4bb98  
 Value of p2 = Address of b = 0x7ffe34a4bb9c  
 Address of p1 = 0x7ffe34a4bba0  
 Address of p2 = 0x7ffe34a4bba8  
 Value of a = 87 87 87  
 Value of b = 4.50 4.50 4.50  

Q2. Program to understand pointer to pointer.

 #include <iostream>  
 using namespace std;  
 int main() {  
   int a = 5;  
   int *pa;  
   int **ppa;  
   pa = &a;  
   ppa = &pa;  
   printf("Address of a = %p\n", &a);  
   printf("Value of pa = Address of a = %p\n", pa);  
   printf("Value of *pa = Value of a = %d\n", *pa);  
   printf("Address of pa = %p\n", &pa);  
   printf("Value of ppa = Address of pa = %p\n", ppa);  
   printf("Value of *ppa = Value of pa = %p\n", *ppa);  
   printf("Value of **ppa = Value of a = %d\n", **ppa);  
   printf("Address of ppa = %p\n", &ppa);  
 }  

OUTPUT:

 Address of a = 0x7ffdc128220c  
 Value of pa = Address of a = 0x7ffdc128220c  
 Value of *pa = Value of a = 5  
 Address of pa = 0x7ffdc1282210  
 Value of ppa = Address of pa = 0x7ffdc1282210  
 Value of *ppa = Value of pa = 0x7ffdc128220c  
 Value of **ppa = Value of a = 5  
 Address of ppa = 0x7ffdc1282218  

Q3. Program to print the value and address of the elements of an array.

 #include <iostream>  
 using namespace std;  
 int main() {  
   int arr[5] = {5, 10, 15, 20, 25};  
   int i;  
   for(i = 0; i < 5; i++) {  
     printf("Value of arr[%d] = %d\t", i, arr[i]);  
     printf("Address of arr[%d] = %p\n", i, &arr[i]);  
   }  
 }  

OUTPUT:

 Value of arr[0] = 5     Address of arr[0] = 0x7ffe3748bc60  
 Value of arr[1] = 10     Address of arr[1] = 0x7ffe3748bc64  
 Value of arr[2] = 15     Address of arr[2] = 0x7ffe3748bc68  
 Value of arr[3] = 20     Address of arr[3] = 0x7ffe3748bc6c  
 Value of arr[4] = 25     Address of arr[4] = 0x7ffe3748bc70  

Q4. Program to print the value and address of elements of an array using pointer.

 #include <iostream>  
 using namespace std;  
 int main() {  
   int arr[5] = {5, 10, 15, 20, 25};  
   int i;  
   for(i = 0; i < 5; i++) {  
     printf("Value of arr[%d] = %d\t", i, *(arr+i));  
     printf("Address of arr[%d] = %p\n", i, arr+i);  
   }  
 }  

OUTPUT:

 Value of arr[0] = 5     Address of arr[0] = 0x7ffc148936f0  
 Value of arr[1] = 10     Address of arr[1] = 0x7ffc148936f4  
 Value of arr[2] = 15     Address of arr[2] = 0x7ffc148936f8  
 Value of arr[3] = 20     Address of arr[3] = 0x7ffc148936fc  
 Value of arr[4] = 25     Address of arr[4] = 0x7ffc14893700  

Q5. Program to call by value.

 #include <iostream>  
 using namespace std;  
 void value(int x, int y);  
 int main() {  
   int a = 5, b = 8;  
   printf("Before calling the function, a = %d and b = %d\n", a, b);  
   value(a, b);  
   printf("After calling the function, a = %d and b = %d\n", a, b);  
 }  
 void value(int x, int y) {  
   x++;  
   y++;  
   printf("Inside function x = %d, y = %d\n", x, y);  
 }  

OUTPUT:

 Before calling the function, a = 5 and b = 8  
 Inside function x = 6, y = 9  
 After calling the function, a = 5 and b = 8  

Q6. Program to call by reference.

 #include <iostream>  
 using namespace std;  
 void ref(int *p, int *q);  
 int main() {  
   int a = 5, b = 8;  
   printf("Before calling a function a = %d and b = %d\n", a, b);  
   ref(&a, &b);  
   printf("After calling a function a = %d and b = %d\n", a, b);  
 }  
 void ref(int *p, int *q) {  
   (*p)++;  
   (*q)++;  
   printf("Inside function *p = %d, *q = %d\n",*p, *q);  
 }  

OUTPUT:

 Before calling a function a = 5 and b = 8  
 Inside function *p = 6, *q = 9  
 After calling a function a = 6 and b = 9  

Q7. Program to show how to return more than one value from a function using call by reference.

 #include <iostream>  
 using namespace std;  
 void func(int x, int y, int *ps, int *pd, int *pp) {  
   *ps = x+y;  
   *pd = x-y;  
   *pp = x*y;  
 }  
 int main() {  
   int a, b, sum, diff, prod;  
   a = 6, b = 4;  
   func(a, b, &sum, &diff, &prod);  
   printf("Sum = %d, Difference = %d, Product = %d\n", sum, diff, prod);  
 }  

OUTPUT:

 Sum = 10, Difference = 2, Product = 24  

Q8. Program to show a function that returns a pointer.

 #include <iostream>  
 using namespace std;  
 int *fun(int *p, int n);  
 int mian() {  
   int arr[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, n, *ptr;  
   n = 5;  
   ptr = fun(arr, n);  
   printf("arr = %p, ptr = %p, *ptr = %d\n", arr, ptr, *ptr);  
 }  
 int *fun(int *p, int n) {  
   p = p+n;  
   return p;  
 }  

Q9. Program to show that changes to the array made inside the function affect the original array.

 #include <iostream>  
 using namespace std;  
 void func(int a[]);  
 int main() {  
   int i, arr[5] = {2, 4, 1, 8, 6};  
   func(arr);  
   printf("Inside main() : ");  
   for(i = 0; i < 5; i++) {  
     printf("%d ", arr[i]);  
   }  
 }  
 void func(int a[]) {  
   int i;  
   printf("Inside func() : ");  
   for(i = 0; i < 5; i++)  
   {  
     a[i] = a[i] + 2;  
     printf("%d ", a[i]);  
   }  
   printf("\n");  
 }  

OUTPUT:

 Inside func() : 4 6 3 10 8   
 Inside main() : 4 6 3 10 8   

Q10. When an array is passed to a function, the receiving argument is declared as a pointer.

 #include <iostream>  
 using namespace std;  
 void func(float f[], int *i, char c[5]);  
 int main() {  
   float f_arr[5] = {1.4, 2.5, 3.7, 4.1, 5.9};  
   int i_arr[5] = {1, 2, 3, 4, 5};  
   char c_arr[5] = {'a', 'b', 'c', 'd', 'e'};  
   printf("Inside main(): ");  
   printf("Size of f_arr = %u\t", sizeof(f_arr));  
   printf("Size of i_arr = %u\t", sizeof(i_arr));  
   printf("Size of c_arr = %u\t", sizeof(c_arr));  
   func(f_arr, i_arr, c_arr);  
 }  
 void func(float f[], int *i, char c[5]) {  
   printf("Inside func(): ");  
   printf("Size of f = %u\t", sizeof(f));  
   printf("Size of i = %u\t", sizeof(i));  
   printf("Size of c = %u\t", sizeof(c));  
 }  

Q11. Program to an array of pointers.

 #include <iostream>  
 using namespace std;  
 int main() {  
   int *pa[3];  
   int i, a = 5, b = 10, c = 15;  
   pa[0] = &a;  
   pa[1] = &b;  
   pa[2] = &c;  
   for(i = 0; i < 3; i++) {  
     printf("pa[%d] = %p\t", i, pa[i]);  
     printf("*pa[%d] = %d\n", i, *pa[i]);  
   }  
 }  

OUTPUT:

 pa[0] = 0x7ffec0c32910     *pa[0] = 5  
 pa[1] = 0x7ffec0c32914     *pa[1] = 10  
 pa[2] = 0x7ffec0c32918     *pa[2] = 15  

-:STRUCTRE:- Q1. Program to display the values of structure members.

 #include <iostream>  
 #include <string.h>  
 using namespace std;  
 struct student {  
   char name[20];  
   int rollno;  
   float marks;  
 };  
 int main() {  
   struct student stu1 = {"Mark", 02, 98};  
   struct student stu2, stu3;  
   strcpy(stu2.name,"Bob");  
   stu2.rollno = 24;  
   stu2.marks = 97;  
   printf("Enter name, rollno and marks for stu3: ");  
   scanf("%s %d %f", stu3.name, &stu3.rollno, &stu3.marks);  
   printf("stu1 : %s %d %.2f\n", stu1.name, stu1.rollno, stu1.marks);  
   printf("stu2 : %s %d %.2f\n", stu2.name, stu2.rollno, stu2.marks);  
   printf("stu3 : %s %d %.2f\n", stu3.name, stu3.rollno, stu3.marks);  
 }  

INPUT:

 Enter name, rollno and marks for stu3: Alice 20 95.5  

OUTPUT:

 stu1 : Mark 2 98.00  
 stu2 : Bob 24 97.00  
 stu3 : Alice 20 95.50  

Q2. Program to assign a structure variable to another structure variable.

 #include <iostream>  
 #include <string.h>  
 using namespace std;  
 struct student {  
   char name[20];  
   int rollno;  
   float marks;  
 };  
 int main() {  
   struct student stu1 = {"Mark", 02, 98}, stu2;  
   stu2 = stu1;  
   printf("stu1 : %s %d %.2f\n", stu1.name, stu1.rollno, stu1.marks);  
   printf("stu2 : %s %d %.2f\n", stu2.name, stu2.rollno, stu2.marks);  
 }  

OUTPUT:

 stu1 : Mark 2 98.00  
 stu2 : Mark 2 98.00  

Q3. Program to understand an array of structures. Q4. Program to understand arrays within structures. Q5. Program to understand pointers to structures.

 #include <iostream>  
 #include <string.h>  
 using namespace std;  
 struct student {  
   char name[20];  
   int rollno;  
   int marks;  
 };  
 int main() {  
   struct student stu = {"Ahad", 1, 48};  
   struct student *ptr = &stu;  
   printf("Name - %s\t", ptr->name);  
   printf("Rollno - %d\t", ptr->rollno);  
   printf("Marks - %d\n", ptr->marks);  
 }  

OUTPUT:

 Name - Ahad     Rollno - 1     Marks - 48  

Q6. Program to understand how to structure members are sent to a function.

 #include <iostream>  
 #include <string.h>  
 using namespace std;  
 struct student {  
   char name[20];  
   int rollno;  
   int marks;  
 };  
 void display(char name[], int rollno, int marks);  
 int main() {  
   struct student stu1 = {"Ahad", 1, 48};  
   struct student stu2;  
   strcpy(stu2.name, "Ahsan");  
   stu2.rollno = 18;  
   stu2.marks = 90;  
   display(stu1.name, stu1.rollno, stu1.marks);  
   display(stu2.name, stu2.rollno, stu2.marks);  
 }  
 void display(char name[], int rollno, int marks)  
 {  
   printf("Name - %s\t", name);  
   printf("Rollno - %d\t", rollno);  
   printf("Marks - %d\n", marks);  
 }  

OUTPUT:

 Name - Ahad     Rollno - 1     Marks - 48  
 Name - Ahsan     Rollno - 18     Marks - 90  

Q7. Program to understand how a structure variable is sent to a function.

 #include <iostream>  
 #include <string.h>  
 using namespace std;  
 struct student {  
   char name[20];  
   int rollno;  
   int marks;  
 };  
 void display(struct student *);  
 void inc_marks(struct student *);  
 int main() {  
   struct student stu1 = {"Waleed", 2, 89};  
   struct student stu2 = {"Umar", 9, 90};  
   inc_marks(&stu1);  
   inc_marks(&stu2);  
   display(&stu1);  
   display(&stu2);  
 }  
 void inc_marks(struct student *stuptr)  
 {  
   (stuptr->marks)++;  
 }  
 void display(struct student *stuptr)  
 {  
   printf("Name - %s\t", stuptr->name);  
   printf("RollNo - %d\t", stuptr->rollno);  
   printf("Marks - %d\n", stuptr->marks);  
 }  

OUTPUT:

 Name - Waleed     RollNo - 2     Marks - 90  
 Name - Umar     RollNo - 9     Marks - 91