Run ID:59489

提交时间:2023-10-28 16:51:02

#include<iostream> #include<cstring> #include<cmath> using namespace std; int main(){ long long m,v=1,sum=0,i; cin>>m; for(i=1;i<=m;i++){ sum+=v; v*=2; } cout<<sum; return 0; }