这道题

//
// Created by 55062 on 2024/3/16.
//
#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
ll n,m,a,b,vv,w,ans[100010],vis[100010],cnt;
struct node{
    ll x,value;
    bool operator<(const node & a) const{
        return value>=a.value;
    }
};
priority_queue<node> q;
vector<ll> v[100010];
void BFS(){
    while(!q.empty()){
        ll x=q.top().x,value=q.top().value;
        q.pop();
        if(x==b){
            cout<<value;
            exit(0);
        }
        for(int i=0;i<v[x].size();i++){
            ll nx=v[x][i];
            if(vis[nx]==0){
                q.push({nx,value+1+(ans[nx]-ans[x])});
                vis[nx]=1;
            }
        }
    }cout<<"No solution";
    exit(0);
}
int main() {
    cin>>n>>m>>a>>b;
    for(int i=0;i<n;i++) cin>>ans[i];
    for(int i=1;i<=m;i++){
        cin>>vv>>w;
        v[vv].push_back(w);
    }vis[a]=1;
    q.push({a,0});
    cout<<"No solution";
    return 0;
}

这是我的蒟蒻代码，求反例呀