题意:从炮台射出一个球,三个及以上颜色相同的会掉落,问最后会掉落多少个球
分析:先从炮台找一个连通块,然后与顶部连接的连通块都不会掉落,剩下的就是炮台射出后跟随掉落的。
#include <bits/stdc++.h> const int N = 100 + 5; char str[N][N]; int H, W, h, w; int ans; bool check(int x, int y) { if (x < 1 || x > H || y < 1 || y > W || (x%2==0 && y==W) || str[x][y] == ‘@‘) return false; return true; } void DFS(int x, int y, char color, int &cnt) { if (!check (x, y)) { return ; } if (color != ‘@‘ && color != str[x][y]) { return ; } cnt++; str[x][y] = ‘@‘; DFS (x - 1, y, color, cnt); DFS (x + 1, y, color, cnt); DFS (x, y - 1, color, cnt); DFS (x, y + 1, color, cnt); if (x & 1) { DFS (x - 1, y - 1, color, cnt); DFS (x + 1, y - 1, color, cnt); } else { DFS (x - 1, y + 1, color, cnt); DFS (x + 1, y + 1, color, cnt); } } int main() { while (scanf ("%d%d%d%d", &H, &W, &h, &w) == 4) { for (int i=1; i<=H; ++i) { scanf ("%s", str[i] + 1); for (int j=1; j<=W; ++j) { if (str[i][j] == ‘E‘) { str[i][j] = ‘@‘; } } } int cnt = 0; DFS (h, w, str[h][w], cnt); int ans = cnt; if (ans < 3) { puts ("0"); continue; } for (int i=1; i<=W; ++i) { DFS (1, i, ‘@‘, cnt); } for (int i=1; i<=H; ++i) { for (int j=1; j<=W; ++j) { if (i % 2 == 0 && j == W) continue; if (str[i][j] != ‘@‘) { ans++; } } } printf ("%d\n", ans); } return 0; }
时间: 2024-11-04 07:55:11