POJ 1979 POJ 3009 AOJ 0033 AOJ 0118 [搜索類題目][0033貪心模擬]
阿新 • • 發佈：2017-07-18
esp ear mes flag push cnblogs front tmp str
/** POJ 1979 BFS */ #include <stdio.h> #include <string.h> #include <iostream> #include <queue> using namespace std; const int N = 20 + 5; int mp[N][N]; int sx,sy; int n, m; int vis[3000]; int dirx[] = {0, 1, 0, -1}; int diry[] = {1, 0, -1, 0}; void solve() { queue<int> Q;int cnt = 1; memset(vis, 0 , sizeof(vis)); while(Q.size()) Q.pop(); Q.push(sx*100 + sy); vis[sx*100 + sy] = 1; while(!Q.empty()) { int tmp = Q.front(); Q.pop(); int x = tmp / 100, y = tmp % 100; for(int i = 0; i < 4; i++) { int nx = x + dirx[i], ny = y + diry[i];if(nx < 0 || nx >= m || ny < 0 || ny >= n || vis[nx*100 + ny] || mp[nx][ny] == 0) continue; vis[nx*100+ny] = 1; cnt++; Q.push(nx*100 + ny); } } printf("%d\n", cnt); } int main() { while(scanf("%d%d", &n, &m), n || m) { getchar();char ch; for(int i = 0; i < m; i++) { for(int j = 0; j < n; j++) { scanf("%c", &ch); if(ch == ‘.‘) mp[i][j] = 1; else if(ch == ‘#‘) mp[i][j] = 0; else if(ch == ‘@‘) { sx = i, sy = j; mp[i][j] = 1; } } getchar(); } solve(); } return 0; }
/** POJ 3009 DFS */ #include <stdio.h> #include <string.h> #include <iostream> using namespace std; const int N = 20 + 5; const int INF = 0x3f3f3f3f; int n, m; int mp[N][N]; int dirx[] = {0, -1, 0, 1}; int diry[] = {1, 0, -1, 0}; int sx,sy,ex,ey; int success; int dfs(int x, int y, int cur, int step) { if(cur >= 10) return 0; for(int i = 0; i < 4; i++) { int nx = x + dirx[i], ny = y + diry[i]; if(nx < 0|| nx >= m || ny < 0 || ny >= n || mp[nx][ny] == 1) continue; if(nx == ex && ny == ey) { success = min(success, step + 1); return 1; } while(nx >= 0 && nx < m && ny >= 0 && ny < n && mp[nx][ny] == 0) { nx += dirx[i]; ny += diry[i]; if(nx == ex && ny == ey) { success = min(success, step + 1); return 1; } } if(nx < 0 || nx >=m || ny < 0 || ny >= n ) continue; if(mp[nx][ny] == 1) { mp[nx][ny] = 0; nx -= dirx[i]; ny -= diry[i]; dfs(nx, ny, cur+1, step+1); nx += dirx[i]; ny += diry[i]; mp[nx][ny] = 1; } } return 0; } int main() { while(scanf("%d%d", &n, &m), n || m) { for(int i = 0; i < m; i++) { for(int j = 0; j < n; j++) { scanf("%d", &mp[i][j]); if(mp[i][j] == 2) { sx = i, sy = j; mp[i][j] = 0; } else if(mp[i][j] == 3) { ex = i, ey = j; mp[i][j] = 0; } } } success = INF; dfs(sx,sy, 0, 0); if(success < INF) printf("%d\n", success); else printf("-1\n"); } return 0; }
/** AOJ 0118 DFS */ #include <stdio.h> #include <string.h> #include <iostream> using namespace std; const int N = 100 + 5; int n,m; int mp[N][N]; int dirx[] = {0, 1, 0, -1}; int diry[] = {1, 0, -1, 0}; int apple, pear, orange; void dfs(int x, int y, int color) { mp[x][y] = 0; for(int i = 0; i < 4; i++) { int nx = x + dirx[i], ny = y + diry[i]; if(nx < 0 || nx >= n || ny < 0 || ny >= m) continue; if(mp[nx][ny] == color) dfs(nx, ny, color); } } int main() { while(scanf("%d%d", &n, &m), n || m) { apple = pear = orange = 0; char ch; getchar(); for(int i = 0; i < n; i++) { for(int j = 0; j < m; j++) { scanf("%c", &ch); if(ch == ‘@‘) mp[i][j] = 1; else if(ch == ‘#‘) mp[i][j] = 2; else if(ch == ‘*‘) mp[i][j] = 3; } getchar(); } for(int i = 0; i < n; i++) { for(int j = 0; j < m; j++) { if(mp[i][j] == 1) { apple++; } else if(mp[i][j] == 2) { pear++; } else if(mp[i][j] == 3) { orange++; } else continue; dfs(i, j, mp[i][j]); } } printf("%d\n", apple+pear+orange); } return 0; }
/** 貪心模擬 先放左再放右，優先選擇大的能放的放 */ #include <stdio.h> #include <string.h> #include <iostream> using namespace std; const int N = 20 + 5; int T; int main() { scanf("%d", &T); while(T--) { int left = 0, right = 0, flag = 0; for(int i = 0; i < 10; i++) { int tmp; scanf("%d", &tmp); if(tmp > left) left =tmp; else if(tmp > right) right = tmp; else flag = 1; } if(flag) printf("NO\n"); else printf("YES\n"); } return 0; }
POJ 1979 POJ 3009 AOJ 0033 AOJ 0118 [搜索類題目][0033貪心模擬]