Solution of URI 1153 :: Simple Factorial

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/**Bismillahir Rahmanir Rahim.**/

#include <stdio.h>
int main()
{
    int N,a,m=1;
    scanf("%d", &N);
    for(a=N;a>=1;a--)
        m*=a;
    printf ("%d\n",m);
    return 0;
}