P1014 Cantor表

#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n;cin>>n;
	int i=1;
	while(i*(i-1)/2<n){
		i++;
	}
	int a,b;
	if((i-1)%2==0){
		a=1;b=i-a;
	}else{
		b=1;a=i-b;
	}
	int start=(i-2)*(i-1)/2+1;
	if(a==1)
	{
		while(start!=n){
			a++;
			b--;
			start++;
		}
		printf("%d/%d",a,b);
	}else{
		while(start!=n){
			b++;
			a--;
			start++;
		}
		printf("%d/%d",a,b);
	}
	return 0;
}

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