学步园

这道题坑在三个地方：

第一，是忽略dij的最外层循环的次数应该是出现的节点的个数，而不是26次；

第二，是忽略了除数为0的情况；

第三，是输入的问题，以后输入单独的字符，都用字符串来处理

代码：

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;

const int N = 30;
const int INF = 0x3fffffff;
int T, M, n, cnt;
int g[N][N], tb[N][N], d[N], vis[N];
bool node[30];

int tim( int sec, int i, int j ) 
{
    if ( tb[i][j] == 0 || sec/tb[i][j]%2 ) return 0;
    return tb[i][j] - sec%tb[i][j];
}
int Dijsktra( int S, int E ) 
{
    int imax, mark, u;
    d[S] = 0;
    memset( vis, 0, sizeof(vis));
    for ( u = 0; u < n; ++u ) {
        imax = INF;
        for ( int i = 0; i < 26; ++i ) if ( !vis[i] && imax > d[i] ) imax = d[mark=i];
        vis[mark] = true;
        //cout << imax << endl;
        for ( int i = 0; i < 26; ++i ) {
            if ( !vis[i] && g[mark][i] > 0 ) {
                int tmp =  tim(d[mark]+g[mark][i], mark, i);
                if ( d[i] > d[mark] + g[mark][i] + tmp ) 
                    d[i] = d[mark] + g[mark][i] + tmp;
            }
        }
    } 
    return d[E];
}
void init() 
{
    for ( int i = 0; i < N; ++i ) {
        d[i] = INF; 
    }
    memset( g, -1, sizeof(g));
    memset( tb, -1, sizeof(tb));
    memset( node, 0, sizeof(node));
    n = cnt = 0;
}
int main()
{
    while(scanf("%d", &T)!= EOF ) {
    while ( T-- ) {
        scanf("%d", &M);
        init();
        char ss[5], ee[5];
        int u, v, dis, rgt;
        while ( M-- ) {
            getchar();
            scanf("%s %s %d %d", ss, ee, &dis, &rgt);
            u = ss[0] - 'a';
            v = ee[0] - 'a';
            if ( !node[u] ) {
                node[u] = true;
                n++;
            }
            if ( !node[v] ) {
                node [v] = true;
                n++;
            }
            g[u][v] = dis, tb[u][v] = rgt;
        }
        getchar();
        scanf("%s%s", ss, ee);
        u = ss[0] - 'a'; v = ee[0] - 'a';
        printf("%d\n", Dijsktra( u, v ));
    }
    }
}