View Code of Problem 73

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int N;
    scanf("%d",&N);
    int i;
    int sum=0,res=1;
    for(i=1;i<N;i++)
    {
         res=(res+1)*2;
    }
    printf("%d",res);

    return 0;
}