C++ 代码

#include<bits/stdc++.h>

using namespace std;

const int N = 40;
int a[N];

int main(){
    int res = 0 ,add = 0 , x;
    while(cin>>x){
        if(x == 0){
            cout<<res<<endl;
            return 0;
        }
        if(x == 1){
            res++ ; add = 0;
        }else{
            add += 2;
            res +=add;
        }
    }
    return 0;
}