day61|Bellman_ford 队列优化算法（又名SPFA）,bellman_ford之判断负权回路,bellman_ford之单源有限最短路

Bellman_ford 队列优化算法（又名SPFA）

94. 城市间货物运输 I (kamacoder.com)

#include <iostream>
#include <vector>
#include <queue>
#include <list>
#include <climits>
using namespace std;

struct Edge { 
    int to;  
    int val; 

    Edge(int t, int w): to(t), val(w) {}  
    
};


int main() {
    int n, m, s, t, v;
    cin >> n >> m;

    vector<list<Edge>> grid(n + 1); 

    vector<int> isInQueue(n + 1);


    for(int i = 0; i < m; i++){
        cin >> s >> t >> v;
        grid[s].push_back(Edge(t, v));
    }

    vector<int> minDist(n + 1 , INT_MAX);
    minDist[1] = 0;

    queue<int> que;
    que.push(1); 

    while (!que.empty()) {

        int cur = que.front(); 
        que.pop();
        isInQueue[cur] = false;
        for (Edge edge : gr