View Code of Problem 73

#include<stdio.h>
#include<stdlib.h>
int main(){
	int N,i,M=1;
	scanf("%d",&N);
	if(N==1) printf("%d",M);
	else{
		for(i=2;i<=N;i++){
		M=(M+1)*2;
		}
	printf("%d",M);
	}

}