题目：蓝桥云课-青蛙吃虫

解题代码：

#include <iostream>
#include<cstring>
#include<algorithm>
using namespace std;const int N=106;int f[N][N];
int a[N]; 
int t,l,r,k,n;int main()
{cin>>t;while(t--){scanf("%d%d%d%d",&n,&l,&r,&k);memset(f,-0x3f,sizeof f);f[0][0]=0;for(int i=1;i<=n;i++) scanf("%d",&a[i]);for(int i=1;i<=n;i++){for(int j=1;j<=k;j++){for(int k=l;k<=r;k++){if(i-k>=0){f[i][j]=max(f[i][j],f[i-k][j-1]+a[i]);}else{break;}}}}int ans=0;for(int i=1;i<=n;i++){for(int j=1;j<=k;j++){ans=max(ans,f[i][j]);//cout<<f[i][j]<<" ";}//cout<<endl;}printf("%d\n",ans);}return 0;
}