#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <string>
#include <cstring>
#include <cmath>
#include <vector>

using namespace std;

int main(void)
{
	int n, m, koraci = 0, x, y;
	cin>>n>>m;
	int brojevi[n], zamjene[m][2];
	int delta[n];
	for(int i = 0; i < n; i++) {
		cin>>brojevi[i];}
	for(int j = 0; j < m; j++) {
			cin>>x>>y;
		zamjene[j][0] = x-1;
		zamjene[j][1] = y-1;	
		;}
	cout<<round(sqrt(m*n));

     return 0;
}