wenbao与分治

 啦啦啦啦啦啦啦啦啦！！！！！！！！！！！

现在想想其实线段树就是运用分治的思想。。。

#include <iostream>
using namespace std;
const int maxn = 1e5+10;
int Max(int x, int y){
    return x > y ? x : y;
}
int a[maxn];
int fenzhi(int *a, int l, int r){
    if(r-l == 1) return a[l];
    int mid = l + (r - l) / 2;
    int ma = Max(fenzhi(a, l, mid), fenzhi(a, mid, r));
    int v = 0, lx = a[mid-1], rx = a[mid];
    for(int i = mid-1; i >= l; i--) lx = Max(lx, v += a[i]);
    v = 0;
    for(int i = mid; i < r; i++) rx = Max(rx, v += a[i]);
    return Max(ma, lx + rx);
}
int main(){
    int t, n; 
    cin >> t;
    while(t--){
        cin >> n;
        for(int i = 0; i < n; i++) cin >> a[i];
        cout<<fenzhi(a, 0, n)<<endl;
    }
    return 0;
}

 

只有不断学习才能进步！