好几天不写程序的结果就是以前的东西都忘得差不多了……o(╯□╰)o
1 #include <iostream> 2 #include <cstdio> 3 #include <cstdlib> 4 #include <cstring> 5 #include <cctype> 6 #include <stack> 7 #include <queue> 8 #include <map> 9 #include <set> 10 #include <vector> 11 #include <cmath> 12 #include <algorithm> 13 #define lson l, m, rt<<1 14 #define rson m+1, r, rt<<1|1 15 using namespace std; 16 typedef long long int LL; 17 const int MAXN = 0x7fffffff; 18 const int MINN = -0x7fffffff; 19 const double eps = 1e-9; 20 const int dir[8][2] = {{0,1},{1,0},{0,-1},{-1,0},{-1,1}, 21 {1,1},{1,-1},{-1,-1}}; 22 const int MAX = 20; 23 int S[MAX], dist[MAX], path[MAX], edge[MAX][MAX]; 24 int n; 25 void Dijkstra(int v0) { 26 int i, j, k; 27 for (i = 0; i <n ; ++i) { 28 dist[i] = edge[v0][i]; S[i] = 0; 29 if (i != v0 && edge[v0][i] != MAXN) path[i] = v0; 30 else path[i] = -1; 31 } 32 S[v0] = 1; dist[v0] = 0; 33 for (i = 0; i < n - 1; ++i) { 34 int Min = MAXN, u = v0; 35 for (j = 0; j < n; ++j) { 36 if (dist[j] < Min && S[j] == 0) { 37 Min = dist[j]; u = j; 38 } 39 } 40 S[u] = 1; 41 for (j = 0; j < n; ++j) { 42 if (S[j] == 0 && edge[u][j] != MAXN) { 43 int tmp = edge[u][j] + dist[u]; 44 if (tmp < dist[j]) { 45 dist[j] = tmp; path[j] = u; 46 } 47 } 48 } 49 } 50 } 51 int main(void){ 52 #ifndef ONLINE_JUDGE 53 freopen("dijkstra.in", "r", stdin); 54 #endif 55 scanf("%d", &n); 56 int u, v, w, i, j, k; 57 memset(edge, 0, sizeof(edge)); 58 while (1) { 59 scanf("%d%d%d", &u, &v, &w); 60 if (u == -1 && v == -1 && w == -1) break; 61 edge[u][v] = w; 62 } 63 for (i = 0; i < n; ++i) { 64 for (j = 0; j < n; ++j) { 65 if (i == j) edge[i][j] = 0; 66 else if (edge[i][j] == 0) edge[i][j] = MAXN; 67 } 68 } 69 Dijkstra(0); 70 for (i = 1; i < n; ++i) { 71 printf("%d\t", dist[i]); 72 int Shortest[MAX]; k = 0; 73 Shortest[k] = i; int po = path[i]; 74 while (po != -1) { 75 Shortest[++k] = po; po = path[po]; 76 } 77 for (j = k; j > 0; --j) { 78 printf("%d->", Shortest[j]); 79 } 80 printf("%d\n", Shortest[0]); 81 } 82 83 return 0; 84 }
这次遇到的问题就是edge的初始化位置写错了，调好久。。
