HDOJ 3790 双权值Dijkstra
时间:2014-04-28 09:34:15
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1 #include <iostream> 2 #include <stdio.h> 3 #include <string.h> 4 #include <cstring> 5 using namespace std; 6 7 const int INF = 1000000; 8 const int MAXSIZE = 1005; 9 10 int map[MAXSIZE][MAXSIZE]; 11 int price[MAXSIZE][MAXSIZE]; 12 int n; 13 14 void Dijkstra(int s,int e){ 15 bool done[MAXSIZE]; 16 int dis[MAXSIZE],co[MAXSIZE]; 17 18 memset(done,0,sizeof(done)); 19 20 for(int i = 0;i <= n;i++) 21 dis[i] = INF; 22 dis[s] = co[s] = 0; 23 24 for(int i = 0;i <= n;i++){//最多执行n+1次操作 25 int pos,minn = INF; 26 for(int j = 0;j <= n;j++){//先找到d[]最小的点 27 if(!done[j] && dis[j] < minn){ 28 minn = dis[j]; 29 pos = j; 30 } 31 } 32 done[pos] = 1;//将该点加入集合 33 for(int j = 0;j <= n;j++){//再更新所有的d[] 34 //if(!done[j] && d[minx] + map[minx][j] < d[j]) 35 //d[j] = d[minx] + map[minx][j]; 36 37 if (!done[j] && map[pos][j] != INF){ 38 //若存在更小的路径,取更小的路径 39 if (dis[j] > dis[pos] + map[pos][j]){ 40 dis[j] = map[pos][j] + dis[pos]; 41 co[j] = price[pos][j] + co[pos]; 42 } 43 //当最短路径相等时候,取价格小的 44 else if (dis[j] == dis[pos] + map[pos][j] && co[j] > co[pos] + price[pos][j]) 45 co[j] = co[pos] + price[pos][j]; 46 } 47 } 48 } 49 printf("%d %d\n",dis[e],co[e]); 50 } 51 52 int main(){ 53 int m,s; 54 int i,j; 55 int p,q,t,pri; 56 int ww,ans; 57 58 while(scanf("%d%d",&n,&m) , n || m){ 59 ans = 100000000; 60 for(i = 0;i < MAXSIZE;i++){ 61 for(j = 0;j < MAXSIZE;j++){ 62 if(i == j) 63 map[i][j] = 0; 64 else 65 map[i][j] = INF; 66 } 67 } 68 while(m--){ 69 scanf("%d%d%d%d",&p,&q,&t,&pri); 70 if(t < map[p][q]){//可能两站间存在多条线路取短的那条路 71 map[p][q] = t; 72 map[q][p] = t; 73 price[p][q] = pri; 74 price[q][p] = pri; 75 } 76 } 77 scanf("%d%d",&ww,&s); 78 map[0][ww] = 0; 79 Dijkstra(0,s);//巧妙之处,加入超级源点0 80 } 81 return 0; 82 }
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