POJ1062昂贵的聘礼[最短路建模]

//
//  main.cpp
//  poj1062
//
//  Created by Candy on 9/13/16.
//  Copyright © 2016 Candy. All rights reserved.
//

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <queue>
#include <cstring>
using namespace std;
const int N=105,INF=1e9;
inline int read(){
    char c=getchar();int x=0,f=1;
    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1;c=getchar();}
    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘;c=getchar();}
    return x;
}
int m,n,l[N],sl[N],p,t,x,val,ans=INF;
struct edge{
    int v,w,ne;
}e[N*N];
int h[N],cnt=0;
inline void ins(int u,int v,int w){
    cnt++;
    e[cnt].v=v;e[cnt].w=w;e[cnt].ne=h[u];h[u]=cnt;
}
int d[N],inq[N],q[N*N],head=1,tail=0;
void spfa(int mn){
    for(int i=1;i<=n;i++) d[i]=INF;
    d[0]=0; inq[0]=1; q[++tail]=0;
    while(head<=tail){
        int u=q[head++];inq[u]=0;
        for(int i=h[u];i;i=e[i].ne){
            int v=e[i].v,w=e[i].w;
            if(mn+m<l[v]||l[v]<mn) continue;//{printf("v %d\n",v);continue;}
            if(d[v]>d[u]+w){
                d[v]=d[u]+w;
                if(!inq[v]){inq[v]=1;q[++tail]=v;}
            }
        }
    }
    ans=min(ans,d[1]);
}
int main(int argc, const char * argv[]) {
    m=read();n=read();
    for(int i=1;i<=n;i++){
        p=read();l[i]=sl[i]=read();x=read();
        ins(0,i,p);
        while(x--){t=read();val=read();ins(t,i,val);}
    }
    sort(sl+1,sl+1+n);
    for(int i=1;i<=n;i++) if(sl[i]<=l[1]) spfa(sl[i]);
    printf("%d",ans);
    return 0;
}