拓扑排序。
深刻体会:ACM比赛的精髓之处不在于学了某个算法或数据结构,而在于知道这个知识点但不知道这个问题可以用这个知识去解决!一看题目,根本想不到是拓扑排序。T_T......
#include<stdio.h> #include<string.h> #include<math.h> #include<vector> #include<algorithm> using namespace std; int mapp[50][50]; char s[1000]; int i, j, k, f; vector<int> abc[1000]; int jz[20][20]; int c[20]; int ff[100][100]; void chushihua() { jz[1][1] = 1; jz[2][1] = 1; jz[2][2] = 1; jz[3][2] = 1; jz[3][3] = 1; jz[4][3] = 1; jz[5][1] = 1; jz[5][4] = 1; jz[6][1] = 1; jz[6][2] = 1; jz[6][4] = 1; jz[6][5] = 1; jz[7][2] = 1; jz[7][3] = 1; jz[7][5] = 1; jz[7][6] = 1; jz[8][3] = 1; jz[8][6] = 1; jz[9][4] = 1; jz[9][7] = 1; jz[10][4] = 1; jz[10][5] = 1; jz[10][7] = 1; jz[10][8] = 1; jz[11][5] = 1; jz[11][6] = 1; jz[11][8] = 1; jz[11][9] = 1; jz[12][6] = 1; jz[12][9] = 1; jz[13][7] = 1; jz[14][7] = 1; jz[14][8] = 1; jz[15][8] = 1; jz[15][9] = 1; jz[16][9] = 1; } int main() { memset(jz, 0, sizeof(jz)); chushihua();int ge; while (~scanf("%s", s)) { for (i = 0; i < 20; i++)abc[i].clear(); memset(ff, 0, sizeof(ff)); if (strcmp("ENDOFINPUT", s) == 0) break; memset(c, 0, sizeof(c)); for (i = 1; i <= 4; i++) for (j = 1; j <= 4; j++) scanf("%d", &mapp[i][j]); for (i = 1; i <= 4; i++) { for (j = 1; j <= 4; j++) { ge = (i - 1) * 4 + j; for (f = 1; f <= 9; f++) { if (jz[ge][f] == 1 && f != mapp[i][j]) { if (ff[mapp[i][j]][f] == 0) { ff[mapp[i][j]][f] = 1; abc[mapp[i][j]].push_back(f); c[f]++; } } } } } scanf("%s", s); int df, summ = 0; while (1) { df = 0; for (i = 1; i <= 9; i++) { if (c[i] == 0) { c[i]--;df = 1;summ++; for (j = 0; j < abc[i].size(); j++) c[abc[i][j]]--; break; } } if (summ == 9){printf("THESE WINDOWS ARE CLEAN ");break;} if (df == 0){printf("THESE WINDOWS ARE BROKEN ");break;} } } return 0; }