#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#define N 10010
using namespace std;
struct Point
{
int x,y;
}Q[N];
struct Node
{
int v,next;
}edge[N*10];
int pre[N], head[N], TN[33][33],tm[33][33];
bool mark[N];
int dir[4][2] = {0,1,1,0,0,-1,-1,0};
int Tm,Tn;
void add_edge( int u, int v, int &num )
{
edge[num].v = v;
edge[num].next = head[u];
head[u] = num++;
}
int get_map( int m, int n, int &k )
{
int u, v;
memset(tm,0,sizeof(tm));
for( int i = 0 ; i < k; i ++ )
{
scanf("%d%d",&v,&u); //注意
tm[u][v] = 1;
}
if( (m*n-k)%2 == 1 ) return -1;
Tn = Tm = 0;
for( int i = 1; i <= m; i ++ )
for( int j = 1; j <= n; j ++ )
{
if( tm[i][j] == 0 )
{
if( (i+j)%2==1 )
{
Q[++Tm].x = i;
Q[Tm].y = j;
}
else TN[i][j] = ++Tn;
}
}
memset(head,-1,sizeof(head));
int num = 0;
for( int i = 1; i <= Tm; i ++ )
{
for( int t = 0; t < 4; t ++ )
{
int x = Q[i].x+dir[t][0];
int y = Q[i].y+dir[t][1];
if( x<=m&&x>=1&&y<=n&&y>=1&&tm[x][y] == 0 )
add_edge(i,TN[x][y]+Tm,num);
}
}
return 0;
}
bool dfs( int u )
{
for( int p = head[u] ; p!=-1 ; p = edge[p].next )
{
int v = edge[p].v;
if( !mark[v] )
{
mark[v] = true;
if( pre[v] == -1 || dfs( pre[v] ) )
{
pre[v] = u;
return true;
}
}
}
return false;
}
bool hungry()
{
if( Tm!=Tn ) return false;
int ans = 0;
memset(pre,-1,sizeof(pre));
for( int i = 1; i <= Tm; i++ )
{
memset(mark,false,sizeof(mark));
if( dfs(i) ) ans++;
}
if( ans == Tm ) return true;
else return false;
}
int main()
{
int m,n,k;
while( scanf("%d%d%d",&m,&n,&k)!=EOF )
{
int tn = get_map(m,n,k);
if( tn == -1 ){ printf("NO\n");continue;}
if( hungry() ) printf("YES\n");
else printf("NO\n");
}
return 0;
poj 2446
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