POJ1364

4 2

1 2 gt 0

2 2 lt 2

if(s[0]=='g')    S3-S0>0    S3-S0>=1  S0-S3<=-1

if(s[0]=='l')    S4-S1<2     S4-S1<=1 

因为图有可能不连通，所以我们添加一个超级源点 n+1 ，然后建n+1到各个顶点的边，权值为0

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <queue>
using namespace std;
#define inf 9999999
#define N 105
#define M 20000
int dis[N],vis[N],head[N],in[N];
int size , n ,m ;
struct Edge
{
    int v,w,next;
    Edge(){}
    Edge(int V,int W,int NEXT):v(V),w(W),next(NEXT){}
}edge[M];

void Init()
{
    size = 0;
    memset(head,-1,sizeof(head));
}

void InsertEdge(int u,int v,int w)
{
    edge[size] = Edge(v,w,head[u]);
    head[u] = size++;
}

bool SPFA()
{
    for(int i=0; i<=n; i++) //建超级源点到其他各点的边 ，保证图联通 
    InsertEdge(n+1,i,0);
    for(int i=0; i<=n+1; i++)
    {
        dis[i] = inf;
        vis[i] = 0;
        in[i] = 0;
    }
    queue<int> Q;
    while(!Q.empty()) Q.pop();
    vis[n+1] = 1 ; dis[n+1] = 0; in[n+1] = 1;

    Q.push(n+1);
    while(!Q.empty())
    {
        int u = Q.front();
        Q.pop();
        vis[u] = 0;
        for(int i=head[u]; i!=-1 ; i = edge[i].next)
        {
            int v = edge[i].v;
            if(dis[v] > dis[u] + edge[i].w)
            {
                dis[v] = dis[u] + edge[i].w;
                if(!vis[v])
                {
                    vis[v] = 1;
                    in[v]++;
                    if(in[v]>(n+2)) return 0; //因为总共n+2个点， 
                    Q.push(v);
                }
            }
        }
    }
    return 1;
}

int main()
{
    while(scanf("%d",&n)!=EOF)
    {
        if(n==0) break;
        scanf("%d",&m);
        Init();
        int u,v,w;
        char s[5];
        while(m--)
        {
            scanf("%d%d%s%d",&u,&v,s,&w);
            if(s[0]=='g') InsertEdge(u+v,u-1,-(w+1));
            if(s[0]=='l') InsertEdge(u-1,u+v,(w-1));
        }
        if(SPFA()) printf("lamentable kingdom
");
        else printf("successful conspiracy
");
    }
    return 0;
}