NOIP2017金秋冲刺训练营杯联赛模拟大奖赛第一轮Day2题解

　　上星期打的...题有点水，好多人都AK了

　　T1排个序贪心就好了

#include<iostream>
#include<cstring>
#include<cstdlib>
#include<cstdio>
#include<algorithm>
#define ll long long
using namespace std;
const int maxn=20;
int n,m,K,x,y;
int f[1<<maxn];
bool v[maxn][maxn],mp[1<<maxn];
void read(int &k)
{
int f=1;k=0;char c=getchar();
while(c<'0'||c>'9')c=='-'&&(f=-1),c=getchar();
while(c<='9'&&c>='0')k=k*10+c-'0',c=getchar();
k*=f;
}
int main()
{
freopen("prison.in","r",stdin);
freopen("prison.out","w",stdout);
read(n);read(m);read(K);
for(int i=1;i<=m;i++)read(x),read(y),v[x][y]=v[y][x]=1;
int state=(1<<n)-1;
for(int i=0;i<=state;i++)
{
int cnt=0;
for(int j=1;j<=n;j++)
if(i&(1<<(j-1)))
for(int k=1;k<j;k++)
if(i&(1<<(k-1)))
cnt+=v[j][k];
if(cnt<=K)mp[i]=1;
}
memset(f,32,sizeof(f));f[0]=0;
for(int i=0;i<=state;i++)
{
int S=i^state;
for(int j=S;j;j=(j-1)&S)
if(mp[j])f[i|j]=min(f[i|j],f[i]+1);
}
printf("%d\n",f[state]);
return 0;
}