HDU3790
最短路径问题
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 23797 Accepted Submission(s):
7091
Problem Description
给你n个点,m条无向边,每条边都有长度d和花费p,给你起点s终点t,要求输出起点到终点的最短距离及其花费,如果最短距离有多条路线,则输出花费最少的。
Input
输入n,m,点的编号是1~n,然后是m行,每行4个数
a,b,d,p,表示a和b之间有一条边,且其长度为d,花费为p。最后一行是两个数
s,t;起点s,终点。n和m为0时输入结束。
(1<n<=1000, 0<m<100000, s != t)
(1<n<=1000, 0<m<100000, s != t)
Output
输出 一行有两个数, 最短距离及其花费。
Sample Input
3 2
1 2 5 6
2 3 4 5
1 3
0 0
Sample Output
9 11
1 //2016.4.21 2 #include <iostream> 3 #include <cstdio> 4 #include <cstring> 5 6 using namespace std; 7 8 const int maxn = 1005; 9 const int inf = 9999999; 10 int Tu_dist[maxn][maxn], Tu_pay[maxn][maxn], dis[maxn], pay[maxn], book[maxn]; 11 int n, m; 12 void dijkstra(int s); 13 14 int main() 15 { 16 while(cin>>n>>m&&n&&m) 17 { 18 for(int i = 0; i <= n; i++) 19 for(int j = 0; j <= n; j++) 20 { 21 Tu_dist[i][j] =inf; 22 Tu_pay[i][j] = inf; 23 } 24 25 int a, b, d, p, s, t; 26 while(m--) 27 { 28 scanf("%d%d%d%d", &a, &b, &d, &p); 29 if(d<Tu_dist[a][b]) 30 { 31 Tu_dist[a][b] = Tu_dist[b][a] = d; 32 Tu_pay[a][b] = Tu_pay[b][a] = p; 33 } 34 } 35 scanf("%d%d", &s, &t); 36 37 dijkstra(s); 38 printf("%d %d\n", dis[t], pay[t]); 39 } 40 return 0; 41 } 42 43 void dijkstra(int s) 44 { 45 int mindist, u, v; 46 for(int i = 1; i <= n; i++) 47 { 48 dis[i] = Tu_dist[s][i]; 49 pay[i] = Tu_pay[s][i]; 50 } 51 52 memset(book, 0, sizeof(book)); 53 book[s] = 1; 54 dis[s] = 0; 55 pay[s] = 0; 56 57 for(int i = 1; i < n; i++) 58 { 59 mindist = inf; 60 for(int j = 1; j <= n; j++) 61 { 62 if(book[j]==0&&dis[j]<mindist) 63 { 64 mindist = dis[j]; 65 u = j; 66 } 67 } 68 book[u] = 1; 69 for(int v = 1; v <= n; v++) 70 { 71 if(!book[v] && Tu_dist[u][v]<inf) 72 { 73 if(dis[v]>dis[u]+Tu_dist[u][v]) 74 { 75 dis[v] = dis[u]+Tu_dist[u][v]; 76 pay[v] = pay[u]+Tu_pay[u][v]; 77 } 78 else if(dis[v]==(dis[u]+Tu_dist[u][v])) 79 pay[v] = (pay[u]+Tu_pay[u][v])<pay[v]?pay[u]+Tu_pay[u][v]:pay[v]; 80 } 81 } 82 } 83 }