#include<bits/stdc++.h>
using namespace std;
signed main()
{
	unsigned int m , t , a , b , c[10000000] , sum = 0 , ans = 0;
	cin >> m;
	for(unsigned int i = 1;i <= m;i++)
	{
		sum += c[i];
		cin >> t;
		if(t == 1)
		{
			cin >> a;
			sum +=  a;
		}
		else if(t == 2)
		{
			cin >> a;
			if(sum < a) ans++;
			else sum -= a;
		}
		else
		{
			cin >> a >> b;
			c[b] += a;
			sum -= a;
		}
	}
	cout << ans << endl;
    return 0;
}