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

int main () {
	int p[100001][4],n;
	double k;
	cin>>n>>k;
	int ans=0;
	for(int i=0;i<=n;i++){
		for(int j=0;j<=n-i;j++){
			//cout<<i<<" "<<j<<endl;
			for(int m=ceil(n*1.0/(n-i-j+1));m<=i+j;m++){
				if(round(i*900000.0/n+j*585000.0/n+m*100000.0/n)==k){
					p[ans][0]=i;
					p[ans][1]=j;
					p[ans][2]=n-i-j;
					p[ans][3]=m;
					ans++;
				}
			}
		}
	}
	if(ans==0){
		cout<<"No solution!";
	}else{
		cout<<ans<<endl;
		for(int i=0;i<ans;i++){
			cout<<p[i][0]<<" "<<p[i][1]<<" "<<p[i][2]<<" "<<p[i][3]<<endl;
		}
	}
	return 0;
}

题目U499016，求优化方法

感谢各位大佬