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;
}