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wenbao與最短路(dfs)

pro pre sin spa ron hihocoder 進步 void none

http://hihocoder.com/problemset/problem/1081

 1 #include <iostream>
 2 #include <stdio.h>
 3 #include <vector>
 4 using namespace std;
 5 const int maxn = 1e3+10;
 6 int n, m, a, b, c, map[maxn][maxn], num[maxn];
 7 vector<int> T[maxn];
 8 void dfs(int x, int sum){
9 if(num[x] == 0 || num[x] > sum) num[x] = sum; 10 else return ; 11 for(int i =0; i < T[x].size(); i++){ 12 dfs(T[x][i], sum + map[x][T[x][i]]); 13 } 14 } 15 int main(){ 16 scanf("%d %d", &n, &m); 17 for(int i = 0; i < n; i++){ 18 scanf("
%d %d %d", &a, &b, &c); 19 if(!map[a][b]){ 20 T[a].push_back(b); 21 T[b].push_back(a); 22 map[a][b] = map[b][a] = c; 23 } 24 else map[a][b] = map[b][a] = min(map[a][b] , c); 25 } 26 dfs(1, 0); 27 printf("%d\n"
, num[m]); 28 return 0; 29 }

http://hihocoder.com/problemset/problem/1089

 1 #include <iostream>
 2 #include <stdio.h>
 3 #include <vector>
 4 using namespace std;
 5 const int maxn = 1e3+10;
 6 int n, m, a, b, c, map[maxn][maxn], map2[maxn][maxn];
 7 vector<int> T[maxn];
 8 void dfs(int start, int x, int sum){
 9     if(map2[start][x] == 0 || map2[start][x] > sum) map2[start][x] = sum;
10     else return ;
11     for(int i =0; i < T[x].size(); i++){
12         dfs(start, T[x][i], sum + map[x][T[x][i]]);
13     }
14 }
15 int main(){
16     scanf("%d %d", &n, &m);
17     for(int i = 0; i < m; i++){
18         scanf("%d %d %d", &a, &b, &c);
19         if(!map[a][b]){
20             T[a].push_back(b);
21             T[b].push_back(a);
22             map[a][b] = map[b][a] = c;
23         }
24         else map[a][b] = map[b][a] = min(map[a][b] , c);
25     }
26     for(int i = 1; i <= n; i++)
27         dfs(i, i, 0), map2[i][i] = 0;
28     for(int i = 1; i <= n; i++){
29         for(int j = 1; j <= n; j++){
30             if(j!=n)
31                 printf("%d ", map2[i][j]);
32             else
33                 printf("%d\n", map2[i][j]);
34         }
35     }
36     return 0;
37 }

只有不斷學習才能進步!

wenbao與最短路(dfs)