最大子段和模板

o（n*logn）

%%#include<iostream>#include<cstdio>#include<cstring>#include<string>#include<iomanip>#include<cstdlib>#include<queue>#include<stack>#include<vector>#include<bitset>#include<algorithm>#include<cmath>#define MM 200005using namespace std;int n,sum,ans=-1e9;int a[MM];int main (){scanf ("%d",&n);for (int i=1;i<=n;i++) scanf ("%d",&a[i]);for (int i=1;i<=n;i++){ans=max(ans,a[i]);sum+=a[i];if (sum<0) sum=0;else ans=max(ans,sum);}printf ("%d",ans);return 0;}