【UESTC 482】Charitable Exchange（优先队列+bfs）

#include<cstdio>
#include<queue>
#include<algorithm>
#include<vector>
#define ll long long
using namespace std;
 
struct node{
    int r,v;
    ll t;
}a[100005];
 
int n,m,cas;
 
int cmp(const node &a, const node &b){
    return a.r<b.r;
}
 
struct cmp2{
    bool operator ()(const node &a, const node &b)
    {
        return a.t>b.t;
    }
};
 
priority_queue<node, vector<node>, cmp2>q;
 
ll bfs(){
    int l=1,i;
    q.push((node){0,1,0});
 
    while(!q.empty()){
        node s=q.top();
        q.pop();
 
        if(s.v>=m)
            return s.t;
 
        for(i=l;i<=n;i++){
            if(s.v>=a[i].r&&s.v<a[i].v)
                q.push((node){0,a[i].v,s.t+a[i].t});
            if(s.v<a[i].r)
                break;
        }
 
        l=i;
    }
    return -1;
}
 
int main(){
    scanf("%d",&cas);
    for(int c=1;c<=cas;c++){
        scanf("%d%d",&n,&m);
        for(int i=1;i<=n;i++)
            scanf("%d%d%d",&a[i].v,&a[i].r,&a[i].t);
 
        while(!q.empty())q.pop();
        sort(a+1,a+1+n,cmp);
 
        printf("Case #%d: %lld\n",c,bfs());
    }
    return 0;
}