DFS+剪枝...
在每次DFS前,当前棋盘的格子数量的一半小于一种颜色的数量时就剪掉
Black And White
Time Limit: 2000/2000 MS (Java/Others) Memory Limit: 512000/512000 K (Java/Others)Total Submission(s): 194 Accepted Submission(s): 50
Special Judge
Problem Description In mathematics, the four color theorem, or the four color map theorem, states that, given any separation of a plane into contiguous regions, producing a figure called a map, no more than four colors are required to color the regions of the map so that no two adjacent regions have the same color.
― Wikipedia, the free encyclopedia
In this problem, you have to solve the 4-color problem. Hey, I’m just joking.
You are asked to solve a similar problem:
Color an N × M chessboard with K colors numbered from 1 to K such that no two adjacent cells have the same color (two cells are adjacent if they share an edge). The i-th color should be used in exactly c i cells.
Matt hopes you can tell him a possible coloring.
Input The first line contains only one integer T (1 ≤ T ≤ 5000), which indicates the number of test cases.
For each test case, the first line contains three integers: N, M, K (0 < N, M ≤ 5, 0 < K ≤ N × M ).
The second line contains K integers c i (c i > 0), denoting the number of cells where the i-th color should be used.
It’s guaranteed that c 1 + c 2 + ? ? ? + c K = N × M .
Output For each test case, the first line contains “Case #x:”, where x is the case number (starting from 1).
In the second line, output “NO” if there is no coloring satisfying the requirements. Otherwise, output “YES” in one line. Each of the following N lines contains M numbers seperated by single whitespace, denoting the color of the cells.
If there are multiple solutions, output any of them.
Sample Input
4 1 5 2 4 1 3 3 4 1 2 2 4 2 3 3 2 2 2 3 2 3 2 2 2
Sample Output
Case #1: NO Case #2: YES 4 3 4 2 1 2 4 3 4 Case #3: YES 1 2 3 2 3 1 Case #4: YES 1 2 2 3 3 1
Source 2014ACM/ICPC亚洲区北京站-重现赛(感谢北师和上交)
#include#include #include #include using namespace std; int n,m,k; int mp[6][6]; struct CC { int num,color; }c[30]; int color[30]; int ccc[30]; bool cmp(CC a,CC b) { return a.num =0&&x =0&&y (cnt+1)/2) return false; } for(int i=0;i =m) {ny=0; nx++;} dfs(nx,ny,cnt-1); if(flag==true) return true; ccc[color[i]]++; mp[x][y]=0; vis[i]=false; } } return false; } int main() { int T_T,cas=1; scanf("%d",&T_T); while(T_T--) { memset(mp,0,sizeof(mp)); scanf("%d%d%d",&n,&m,&k); for(int i=0;i (((n+1)/2)*((m+1)/2)+(n/2)*(m/2))) { puts("NO"); continue; } int pos=0; for(int i=0;i