题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1498
50 years, 50 colors
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1918 Accepted Submission(s):
1058
balloons floating around the campus, it's so nice, isn't it? To celebrate this
meaningful day, the ACM team of HDU hold some fuuny games. Especially, there
will be a game named "crashing color balloons".
There will be a n*n
matrix board on the ground, and each grid will have a color balloon in it.And
the color of the ballon will be in the range of [1, 50].After the referee shouts
"go!",you can begin to crash the balloons.Every time you can only choose one
kind of balloon to crash, we define that the two balloons with the same color
belong to the same kind.What's more, each time you can only choose a single row
or column of balloon, and crash the balloons that with the color you had chosen.
Of course, a lot of students are waiting to play this game, so we just give
every student k times to crash the balloons.
Here comes the problem:
which kind of balloon is impossible to be all crashed by a student in k
times.
begins with two integers n, k. n is the number of rows and columns of the
balloons (1 <= n <= 100), and k is the times that ginving to each
student(0 < k <= n).Follow a matrix A of n*n, where Aij denote the color
of the ballon in the i row, j column.Input ends with n = k = 0.
colors of which are impossible to be crashed by a student in k times. If there
is no choice, print "-1".
#include <iostream>
#include <cstdio>
#include <cstring> using namespace std; int n,m;
int vis[],Map[][],ok[],cc[]; bool Find(int x,int now)
{
for (int i=; i<=n; i++)
{
if (!vis[i]&&Map[x][i]==now)
{
vis[i]=;
if (!ok[i])
{
ok[i]=x;
return true;
}
else
{
if (Find(ok[i],now))
{
ok[i]=x;
return true;
}
}
}
}
return false;
} int main()
{
int flag,ans,s[];
while (~scanf("%d%d",&n,&m))
{
flag=;
memset(cc,,sizeof(cc));
memset(Map,,sizeof(Map));
if (n==&&m==)
break;
for (int i=; i<=n; i++)
{
for (int j=; j<=n; j++)
{
scanf("%d",&Map[i][j]);
cc[Map[i][j]]=;//记录这个颜色出现过
}
}
memset(ok,,sizeof(ok));
int k=;
for (int i=; i<=; i++)
{
memset(ok,,sizeof(ok));
ans=;
if (cc[i]==) //判断颜色是否出现过,加入这里不进行标记的话最后输出的是没有被刷完的颜色数字,就会输出一些乱七八糟的东西
{
for (int j=; j<=n; j++)
{
memset(vis,,sizeof(vis));
if (Find(j,i))
ans++;
}
if (ans>m) //如果最大匹配数大于m次的话就是刷不完的
{
s[++k]=i;
flag=;
}
}
}
if (flag==)
printf ("-1\n");
else
{
for (int i=; i<k; i++) //控制输出格式
{
printf ("%d ",s[i]);
}
printf ("%d\n",s[k]);
}
}
return ;
}