Question

Write a short main program that reads an integer n from standard input and prints (to standard output) n lines of * characters. The number of *’s per line should double each time, starting with 1. E.g., if n = 5, the output should be as follows:

*
**
****
********
****************

Answer 1

#include<stdio.h>
#include<math.h>
void main()                              // main function
{
    int n, i, j, x;                      // declaration of variables
    
    printf("Enter an integer: ");        
    scanf("%d", &n);                     // taking n as user input

    x = pow(2, n);                       // calculating 2^n
                       
    for(i=1; i<x; i*=2)                  // outer loop is running n times
        {
            for(j=1; j<=i; j++)          // inner loop for printing the * 's
                printf("*");             // printing " * "
            printf("\n");                // new line after each iteration of outer loop
        }
}

Output: