我没实力。

#include<bits/stdc++.h>
#define endl '\n'
#define int long long
using namespace std;
const int N = 105;
int n,m,st,en,u,v,c,t,cmin[N][N * N],ans,minn = INT_MAX;
bool vis[N];
struct edge{int v,c,t;};
vector<edge> g[N];
queue<int> q;
void spfa(int s){
	memset(cmin,0x7f,sizeof(cmin));
	q.push(s);for(int i = 1;i <= 10000;i++)cmin[st][i] = 0;vis[s] = true;
	while(!q.empty()){
		int u = q.front();q.pop();vis[s] = false;
		for(int i = 0;i < g[u].size();i++){
			int v = g[u][i].v,c = g[u][i].c,t = g[u][i].t;
			for(int j = 0;j <= 10000 - c;j++){
				if(cmin[u][j] + t < cmin[v][c + j]){
					cmin[v][c + j] = cmin[u][j] + t;
					if(!vis[v])q.push(v),vis[v] = true;
				}
			}
		}
	}
}
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin >> n >> m >> st >> en;
	for(int i = 1;i <= m;i++)cin >> u >> v >> c >> t,g[u].push_back({v,c,t}),g[v].push_back({u,c,t});
	spfa(st);
	for(int j = 0;j <= 10000;j++){
		if(cmin[en][j] >= minn)continue;
		minn = cmin[en][j];
		ans++;
	}
	cout << ans;
}