蓝桥杯 第39级台阶

#include<iostream>#include<set>#include<cstdlib>#include<ctime>#include<vector>#include<string>#include<algorithm>#include<cstdio>#include<sstream>#include<algorithm>#include<map>using namespace std;int cnt=0;void f(int cur,int sum){    if(cur>39) return ;    if(cur==39) {if(sum%2==0) cnt++;return ;}    f(cur+1,sum+1);    f(cur+2,sum+1);}int main(){    f(0,0);    cout<<cnt<<endl;    return 0;}