Run ID:156197
提交时间:2026-06-27 09:39:37
#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ long long a[41]={0,1,2,4},n; cin>>n; for(int i=4;i<=n;i++){ a[i]=2*a[i-1]; }cout<<a[n]; return 0; }