根据二叉树的性质,运用双指针

#include<iostream>
#define N 100010
using namespace std;
typedef long long LL;
int main()
{
    int n,q[N];
    scanf("%d",&n);
    for(int i = 1;i <= n;i ++)  scanf("%d",&q[i]);

    LL maxs = -1e18;
    int depth = 0;
    for(int d = 1, i = 1;i <= n;d ++ , i *= 2)//d表示深度,i表示每一层的起点
    {
        LL s = 0;
        for(int j = i;j < i + (1 << d - 1) && j <= n;j ++)
            s += q[j];
        if(s > maxs)
        {
            maxs = s;
            depth = d;
        }
    }
    printf("%d\n",depth);
}