ZOJ 2526 FatMouse and JavaBean II

用的dijkstra来做的,加了记录最短路径数量,优先队列取的是最短距离中的最大豆子数的点来松弛.

#include <iostream>#include <cstdio>#include <memory.h>#include <queue>using namespace std;const int maxn = 500;struct edge{int v, w, next;}es[maxn * 3];struct node{int i, v, jbs;node(int ii = 0, int vv = 0, int jbss = 0):i(ii),v(vv),jbs(jbss){}bool operator<(const node & rhs)const{return v > rhs.v || (v == rhs.v && jbs < rhs.jbs);//按照距离最短优先,相等时则按照豆子数最多优先的规则来松弛}};int head[maxn], dis[maxn], pathCnt[maxn], javaBeans[maxn], maxJbs[maxn], fa[maxn], n, m, s, e;bool vis[maxn];void dijkstra(){memset(vis, 0, sizeof(vis));memset(fa, -1, sizeof(fa));memset(maxJbs, 0, sizeof(maxJbs));memset(dis, 0X20, sizeof(dis));memset(pathCnt, 0, sizeof(pathCnt));priority_queue<node> q;q.push(node(s, 0, javaBeans[s]));maxJbs[s] = javaBeans[s];dis[s] = 0;pathCnt[s] = 1;while (q.size()){node t = q.top();q.pop();if(vis[t.i])continue;if(t.i == e)break;vis[t.i] = 1;for (int ne = head[t.i]; ne != -1; ne = es[ne].next){int v = es[ne].v, w = es[ne].w, jbs = t.jbs;if(dis[v] > dis[t.i] + w && !vis[v]){pathCnt[v] = pathCnt[t.i];dis[v] = dis[t.i] + w;maxJbs[v] = jbs + javaBeans[v];fa[v] = t.i;q.push(node(v, dis[v], maxJbs[v]));}else if(dis[v] == dis[t.i] + w){pathCnt[v] += pathCnt[t.i]; //累加最短路数量if(maxJbs[v] < jbs + javaBeans[v]){maxJbs[v] = jbs + javaBeans[v];fa[v] = t.i;q.push(node(v, dis[v], maxJbs[v]));}}}}}void addEdge(int u, int v, int w, int eidx){es[eidx].v = v;es[eidx].w = w;es[eidx].next = head[u];head[u] = eidx;}void printPath(int v){if(fa[v] == -1){printf("%d", v);return;}printPath(fa[v]);printf(" %d", v);}int main(){while (~scanf("%d %d %d %d", &n, &m, &s, &e)){memset(head, -1, sizeof(head));for (int i = 0; i < n; ++i){scanf("%d", &javaBeans[i]);}int eidx = 0;for (int i = 0; i < m; ++i){int u, v, w;scanf("%d%d%d", &u, &v, &w);addEdge(u, v, w, eidx++);addEdge(v, u, w, eidx++);}dijkstra();printf("%d %d\n", pathCnt[e] ,maxJbs[e]);printPath(e);printf("\n");}return 0;}