其实是假贪心，正解要dp一下……

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 111111;

int n, m;
struct aaa{
	int x, y;
}a[N];

ll dp[N], ans;

int main(){
	cin>>n>>m;
	for(int i=0;i<n;i++) cin>>a[i].x>>a[i].y;
	
	for(int i=0;i<n;i++)
	for(int j=m-a[i].x;j>=0;j--)
	dp[j+a[i].x] = max(dp[j] + a[i].y, dp[j+a[i].x]);
    cout<<dp[m]<<endl; return 0;
}