Write a program that: 1. Prompts the user to input two positive numbers in a range. 2. Using nested for loops, outputs the rows as shown below. NOTE: Be sure to check for valid inputs. For example (sample user inputs are shown with an underline): Enter two positive integers in the range 1-20: 3 4 +++ +++ +++ +++

To check for valid values, we need to use infinite loop that will exit only if the user enter values within the range. Then we need to use nested loop to print the given pattern, the inner loop is handle by first input value and outer loop is handle by second input value.

The required C program code is given below:

#include <stdio.h>

int main()
{
    int n1, n2, i, j;
    while(1){
        printf( "Enter two positive integers in the range 1-20: " );
        scanf( "%d%d", &n1, &n2);
        if((n1>=1&&n1<=20)&&(n2>=1&&n2<=20))
        break;
        else
        printf("Input is not valid! Try again\n");
    }
    for(i=1; i<=n2; i++)
    {
        for(j=1; j<=n1; j++)
        {
            printf("+");
        }
        printf("\n");
    }

    return 0;
}