cf1058b 点是否在一个矩形里

判断点是否在一个矩形里   用点和4条直线的关系

http://codeforces.com/contest/1058/problem/B

#include<bits/stdc++.h>
using namespace std;

#define ll long long
#define pb push_back
#define mp make_pair
#define all(v) v.begin(),v.end()
#define fi first
#define se second

const int N =1e5+5;
const ll mod = 1e9+7;
const int INF = 1E8+4;
 int n,d;
//http://codeforces.com/contest/1058/problem/B
//判断点是否在一个矩形里   用点和4条直线的关系
bool c(int x,int y){
    if(x-y<-d)return false;
    if(x-y>d)return false;
    if(x+y<d)return false;
    if(x+y>2*n-d)return false;
    return true;
}
int main(){
    cin>>n>>d;
    int m;
    cin>>m;
    while(m--){
        int a,v;
        cin>>a>>v;
        if(c(a,v))cout<<"YES"<<endl;
        else cout<<"NO"<<endl;
    }
    return 0;
}