1155. Can I Post the lette

#include "iostream"#include "memory.h"#include "cstdio"using namespace std;int road[201][201];int n, m;/*利用弗洛伊德算法来解这道题,如果两个城市可以连通，则其距离为0*/inline void floyd(){for (int i = 0; i < n; i++){for (int j = 0; j < n; j++){for (int k = 0; k < n; k++){if (road[j][k] > (road[j][i] + road[i][k])){road[j][k] = road[j][i] + road[i][k];}}}}}int main(){while (cin >> n && n){if (0 == n)break;for (int i = 0; i < 201; i++){for (int j = 0; j < 201; j++){road[i][j] = 100;}road[i][i] = 0;}cin >> m;for (int i = 0; i < m; i++){int a, b;cin >> a >> b;road[a][b] = 0;road[b][a] = 0;}floyd();if (road[0][n - 1] == 0){printf("I can post the letter\n");}else{printf("I can't post the letter\n");}}return 0;}