POJ 1154 解题报告

来源：互联网发布：电子乐器软件编辑：程序博客网时间：2024/04/29 07:34

这道题是普通的DFS，不需要优化就可以通过。

thestoryofsnow1154Accepted164K32MSC++1326B

/* ID: thestor1 LANG: C++ TASK: poj1154 */#include <iostream>#include <fstream>#include <cmath>#include <cstdio>#include <cstring>#include <limits>#include <string>#include <vector>#include <list>#include <set>#include <map>#include <queue>#include <stack>#include <algorithm>#include <cassert>using namespace std;const int MAXR = 20;// There is '\0' in the endconst int MAXC = 20 + 1;int neighbors[4][2] = {{-1, 0}, {0, 1}, {1, 0}, {0, -1}};void dfs(char board[][MAXC], int r, int c, const int R, const int C, bool visited[], int p, int &maxp) {int i = board[r][c] - 'A';if (visited[i]) {return;}visited[i] = true;p++;if (p > maxp) {maxp = p;}for (int d = 0; d < 4; ++d) {int nr = r + neighbors[d][0];int nc = c + neighbors[d][1];if (0 <= nr && nr < R && 0 <= nc && nc < C) {dfs(board, nr, nc, R, C, visited, p, maxp);}}visited[i] = false;}int main(){char board[MAXR][MAXC];int R, C;scanf("%d%d", &R, &C);for (int r = 0; r < R; ++r) {scanf("%s", board[r]);}// printf("[debug]board:\n");// for (int r = 0; r < R; ++r) {// printf("[%s]\n", board[r]);// }bool visited[26];for (int i = 0; i < 26; ++i) {visited[i] = false;}int maxp = 0;dfs(board, 0, 0, R, C, visited, 0, maxp);printf("%d\n", maxp);return 0;}

0 0