51 lines
1.1 KiB
C++
51 lines
1.1 KiB
C++
#include <iostream>
|
|
#include <cstring>
|
|
#include <cstdlib>
|
|
#include<cstdio>
|
|
#include <queue>
|
|
#include <set>
|
|
#include <vector>
|
|
#include <cmath>
|
|
#include <algorithm>
|
|
#define INF 2000000000
|
|
using namespace std;
|
|
typedef long long ll;
|
|
const int MAX_E=10000;
|
|
const int MAX_N=1005;
|
|
const int MAX_K=3000;
|
|
const int MAXN=10010;
|
|
bool judge(int sum,int y,int k)
|
|
{
|
|
int mid1=(k-1)*k/2;
|
|
int mid2=sum-mid1;
|
|
if(mid2<=k-1) return false;
|
|
if(y>k-1&&y!=mid2) return true;
|
|
if(y<=k-1){
|
|
if(k-y<=mid2-(k+1)) return true;
|
|
else return false;
|
|
}
|
|
if(y==mid2){
|
|
if(mid2-(k-1)>=3) return true;
|
|
else return false;
|
|
}
|
|
}
|
|
int main()
|
|
{
|
|
int n,k,T,mm;
|
|
bool flag;
|
|
while(scanf("%d%d",&n,&k)!=EOF){
|
|
int c1=(int)sqrt((double)k*(k-1)/2);
|
|
int c2=(int)sqrt((double)n);
|
|
flag=0;
|
|
for(int i=c1;i<=c2;i++){
|
|
if((k*(k-1)/2<=i*i)&&(i*i<=n-1)&&judge(i*i,n-i*i,k-1)){
|
|
flag=1;
|
|
break;
|
|
}
|
|
}
|
|
if(flag==1) printf("YES\n");
|
|
else printf("NO\n");
|
|
}
|
|
return 0;
|
|
}
|