#include<bits/stdc++.h>
#define ll long long 
using namespace std;
inline ll rd(){
   ll s=0;
   char ch=getchar();
   while(ch<'0'||ch>'9')ch=getchar();
   while(ch>='0'&&ch<='9') s=s*10+ch-'0',ch=getchar();
   return s;
}
void wt(ll x){
	if(x>9) wt(x/10);
	putchar(x%10+'0');
	return;
}
ll a,b,c,x;
int main(){
	a=rd(),b=rd(),c=rd();
	while(1){
		x++;
		if(a-x>=0) a-=x;
		else {x--;break;}
		if(b-x>=0) b-=x;
		else {x--;break;}
	}
	while(1){
		x++;
		if(a+c-x>=0) c-=(x-a),a=0;
		else {x--;break;}
		if(b+c-x>=0) c-=(x-b),b=0;
		else {x--;break;}
	}
	wt(x);
	return 0;
}

求助