Submission #1167313

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Source Code Expand

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

#define fo(i,s,t) for(int i = s; i <= t; ++ i)
#define fd(i,s,t) for(int i = s; i >= t; -- i)
#define go(i,s) for(int i = head[s]; i; i = e[i].next)
#define pb push_back
#define mp make_pair

int x, l, r, mid, ans;

int main()
{
	cin >> x;
	l = 1; r = x;
	while(l <= r)
	{
		mid = l+r >> 1;
		if((long long)(mid+1)*mid/2ll>=x) ans = mid, r = mid - 1;
		else l = mid + 1;
	}
	printf("%d\n",ans);
	return 0;
}

Submission Info

Judge Result