Til the Cows Come Home POJ - 2387 (dijkstra模板)
题目链接：https://cn.vjudge.net/problem/POJ-2387#author=dusenlin
注意：输入的时候，两点之间可能有多条边，选则边权最小的
1 #include <iostream> 2 #include <cstring> 3 #include <cstdio> 4 #include <queue> 5 #include <stack> 6 #include <algorithm> 7 #include <cmath> 8 #include <map> 9 #define mem(a,b) memset(a,b,sizeof(a)); 10 using namespace std; 11 #define INF 0x3f3f3f3f 12 typedef long long ll; 13 int dir[4][2] = {0,1,0,-1,1,0,-1,0}; 14 const int maxn = 5000005; 15 int t,n,edge[1005][1005],d[1005],vis[1005]; 16 void Dijkstra(int s) { 17 mem(vis,0); 18 mem(d,INF); 19 d[1] = 0; 20 for(int i = 1; i <= n; i++) { 21 int maxn = INF,x; 22 for(int j = 1; j <= n; j++) { 23 if(d[j] < maxn&&!vis[j]) { 24 maxn = d[j]; 25 x = j; 26 } 27 } 28 vis[x] = 1; 29 for(int j = 1; j <= n; j++) { 30 d[j] = min(d[j],d[x]+edge[x][j]); 31 } 32 } 33 } 34 int main(){ 35 cin >> t >>n; 36 int a,b,c; 37 mem(edge,INF); 38 for(int i = 0; i < t; i++) { 39 cin >> a >> b >> c; 40 if(c < edge[a][b]){ 41 edge[a][b] = c; 42 edge[b][a] = c; 43 } 44 } 45 Dijkstra(1); 46 cout << d[n] << endl; 47 return 0; 48 }
