最大子段和

简单实现，注意递推关系的选取！

#include <iostream>#include <cmath>#include <algorithm>using namespace std;int a[6] = {-2,11,-4,13,-5,-2};//int ans[10] = {0};//ans[i]表示的是从a0开始到ai必须以a[i]为子段的结尾的这一段中最大子段和为ans[i];即在a数组中第i位为结尾的往前连续的x项最大和为ans[i]//int trace[10] = {0};int ans = 0;int sum = 0;int trace = 0;int main() {    if(a[0] > 0) ans = a[0];    else ans = 0;    for (int i = 1; i < 6; ++i) {//        ans = max(ans+a[i],a[i]);        ans = (ans+a[i] > a[i])?(ans+a[i]):a[i] ;        if (ans > sum){            sum = ans;            trace = i;        }    }    cout << sum << endl;    while (sum){        sum -= a[trace];        cout << a[trace--] << " ";    }    return 0;}