代码如下:
#include<bits/stdc++.h>
using namespace std;
#define mm(a,x) memset(a,x,sizeof a)
#define mk make_pair
#define ll long long
#define pii pair<int,int>
#define inf 0x3f3f3f3f
#define lowbit(x) (x) & (-x)
const int N = 1010;
int n;
int a[N];
int f[N];
/*
状态表示：f[i] :以a[i]结尾的最大上升子序列
状态转移：
if(a[j] < a[i])
f[i] = f[j] + a[i](1<j<i)
初始化：
f[i] = a[i]
*/
int main() {
cin >> n;
for(int i = 1; i <= n; i ++ ) cin >> a[i];
int res = 0;
for(int i = 1; i <= n; i ++ ){
f[i] = a[i];
for(int j = 1; j < i; j ++ ){
if(a[j] < a[i]){
f[i] = max(f[i],f[j] + a[i]);
}
}
res = max(res,f[i]);
}
cout<<res;
return 0;
} 
