C Program to Generate Multiplication Table

The program below takes an integer input from the user and generates the multiplication tables up to 10.

Multiplication Table Up to 10

#include <stdio.h>
int main() {
  int n;
  printf("Enter an integer: ");
  scanf("%d", &n);

  for (int i = 1; i <= 10; ++i) {
    printf("%d * %d = %d \n", n, i, n * i);
  }
  return 0;
}

Output

Enter an integer: 9
9 * 1 = 9
9 * 2 = 18
9 * 3 = 27
9 * 4 = 36
9 * 5 = 45
9 * 6 = 54
9 * 7 = 63
9 * 8 = 72
9 * 9 = 81
9 * 10 = 90

Here, the user input is stored in the int variable n. Then, we use a for loop to print the multiplication table up to 10.

for (i = 1; i <= 10; ++i) {
  printf("%d * %d = %d \n", n, i, n * i);
}

The loop runs from i = 1 to i = 10. In each iteration of the loop, n * i is printed.

Here's a little modification of the above program to generate the multiplication table up to a range (where range is also a positive integer entered by the user).

Multiplication Table Up to a range

#include <stdio.h>
int main() {

  int n, i, range;
  printf("Enter an integer: ");
  scanf("%d", &n);

  // prompt user for positive range
  do {
    printf("Enter the range (positive integer): ");
    scanf("%d", &range);
  } while (range <= 0);

  for (i = 1; i <= range; ++i) {
    printf("%d * %d = %d \n", n, i, n * i);
  }

  return 0;
}

Output

Enter an integer: 12
Enter the range (positive integer): -8
Enter the range (positive integer): 8
12 * 1 = 12 
12 * 2 = 24 
12 * 3 = 36 
12 * 4 = 48 
12 * 5 = 60 
12 * 6 = 72 
12 * 7 = 84 
12 * 8 = 96 

Here, we have used a do...while loop to prompt the user for a positive range.

// prompt user for positive range
do {
  printf("Enter the range (positive integer): ");
  scanf("%d", &range);
} while (range <= 0);

If the value of range is negative, the loop iterates again to ask the user to enter a positive number. Once a positive range has been entered, we print the multiplication table.