Killtime

#include<stdio.h>
#include<vector>
using namespace std;
int n,m,k;
int st,sp;
struct edge{
    int v,c,w;
};

vector<edge> adj[310];
int dp[310][2010];
int recur(int u,int t){
    if(dp[u][t] != -1)return dp[u][t];
    int maxa = ( u == sp ? 0 : -2e9 );
    for(int i = 0 ; i < adj[u].size();i++){
        int v = adj[u][i].v;
        int c = adj[u][i].c;
        int w = adj[u][i].w;
        if(t - w >= 0)maxa = max(maxa,recur(v,t - w) + c);
    }
//  printf("test %d %d : %d\n",u,t,maxa);
    return dp[u][t] = maxa;
}

int main()
{
    for(int i=0;i<310;i++)for(int j=0;j<2010;j++)dp[i][j] = -1;
    scanf("%d %d %d",&n,&m,&k);
    scanf("%d %d",&st,&sp);
    for(int i=1;i<=m;i++){
        int u,v,c,w;
        scanf("%d %d %d %d",&u,&v,&c,&w);
        adj[u].push_back({v,c,w});
        adj[v].push_back({u,c,w});
    }
    int ans = recur(st,k);
    if(ans > 0){
        printf("%d",ans);
    }else{
        printf("Impossible");
    }
    return 0;
}