#include<iostream>
using namespace std;
int m,t,a,b,ans,money,cnt,doh[1000005];
int main(){
	ios::sync_with_stdio(0);
	cin>>m;
	for(int i=0;i<m;i++){
	    cin>>t;
		if(doh[i+1]>0)money+=doh[i+1]; 
		if(t==1) {
			cin>>a;
			money+=a;
		}
		else if(t==2){
			cin>>a;
			if(a>money) ans++,/*cout<<"+1\n"*/;
			else money-=a;
		}
		else{
			cin>>a>>b;
			money-=a;
		    doh[b]+=a;
		}
	    //cout<<"余额："<<money<<"\n";
	}
	cout<<ans;
}