hdu1688 什么都不说了， 自己还是太水

#include <iostream>#include <cstring>#include <algorithm>#include <queue>#include <vector>#include <cstdio>using namespace std;const int inf = 1<<30;const int maxn = 1010;struct Edge {    int to, w;};struct node {    int v,dist;    int mark;    bool friend operator < (const node &a, const node &b) {         if(a.dist != b.dist)            return a.dist > b.dist;         return a.v > b.v;    }};priority_queue<node>Q;vector<Edge>gra[maxn*10];int dp[maxn][3];int vis[maxn][3];int dis[maxn][3];int T,N,M,A,B,L;void init() {    for(int i = 0; i < maxn; i++) {        dp[i][1] = dp[i][2] = 0;        vis[i][1] = vis[i][2] = 0;        dis[i][1] = dis[i][2] = inf;    }}void Dijstra(int st, int ed) {    dis[st][1] = 0;    dp[st][1]= 1;    node q, p;    p.dist = 0;    p.mark = 1;    p.v = st;    Q.push(p);    while(!Q.empty()) {        q = Q.top();        Q.pop();        if(vis[q.v][q.mark])            continue;        vis[q.v][q.mark] = 1;        for(int i = 0; i < gra[q.v].size(); i++){            int vv = gra[q.v][i].to;            int ww = gra[q.v][i].w;            if(!vis[vv][1] && dis[vv][1] > q.dist + ww) {                if(dis[vv][1] != inf) {                    dis[vv][2] = dis[vv][1];                    dp[vv][2] = dp[vv][1];                    p.dist = dis[vv][2];                    p.mark = 2;                    p.v = vv;                    Q.push(p);                }                dis[vv][1] = q.dist + ww;                dp[vv][1] = dp[q.v][q.mark];                p.mark = 1;                p.dist = dis[vv][1];                p.v = vv;                Q.push(p);            }            else if(!vis[vv][1]&& dis[vv][1]== q.dist + ww)            {                dp[vv][1] += dp[q.v][q.mark];            }            else if(!vis[vv][2] && dis[vv][2] > q.dist + ww) {                dis[vv][2] = q.dist + ww;                dp[vv][2] = dp[q.v][q.mark];                p.mark = 2;                p.dist = dis[vv][2];                p.v = vv;                Q.push(p);            }            else if(!vis[vv][2] && dis[vv][2] == q.dist + ww)            {                dp[vv][2] += dp[q.v][q.mark];            }        }    }}int main(){    scanf("%d", &T);    Edge tem;    int st, ed;    while(T--) {        init();        for(int i = 0; i < maxn*10; i++) {            gra[i].clear();        }        scanf("%d%d", &N, &M);        for(int i = 0; i < M; i++) {        scanf("%d%d%d", &A, &B, &L);            tem.to = B;            tem.w = L;            gra[A].push_back(tem);        }        scanf("%d%d", &st, &ed);        Dijstra(st, ed);        if(dis[ed][1] + 1 == dis[ed][2])            printf("%d\n", dp[ed][1] + dp[ed][2]);        else            printf("%d\n", dp[ed][1]);    }    return 0;}