Write a C program to calculate the multiplication of first n

Write a C program to calculate the multiplication of first n numbers. Use a do-while statement.   

EX: enter a positive interger : 5

the multiplication of the first 5 integers is 120.

(1*2*3*4*5=120)

Solution

Solution.c

#include <stdio.h>//header file for input output function
int main()
{//main function
    int n, i, sum = 1;
    do{//do while loop
    printf(\"Enter a positive integer: \");
    scanf(\"%d\",&n);//key board inputting
sum = 1;
    for(i=1; i <= n; ++i)
    {
        sum *= i;   // sum = sum*i;
    }
printf(\"multiplication of   %d natural numbers is %d \ \",n,sum);  
}while(n>0);
printf(\"please enter only positive numbers\");
    return 0;
}

output

sh-4.3$ main                                                                                                                                                             

Enter a positive integer: 5                                                                                                                                              

multiplication of   5 natural numbers is  120                                                                                                                            

Enter a positive integer: 6                                                                                                                                              

multiplication of   6 natural numbers is  720                                                                                                                            

Enter a positive integer: -1                                                                                                                                             

multiplication of   -1 natural numbers is  1                                                                                                                             

please enter only positive numbers