#include <cstdio>

     #include <cstdlib>

     #include <cmath>

     #include <cstring>

     #include <string>

     #include <algorithm>

     #include <iostream>

     using namespace std;

     #define ll long long

     const int maxn=2e5+;

     const int inf=1e9;

     int sum1,tot1;

     int f[maxn],g;

     int main()

     {

         int n,a,b,i,j,v;

         scanf("%d",&n);

         for (i=;i<=n;i++)

         {

             scanf("%d",&a);

             if (a== || a==)

                 scanf("%d",&b);

             if (a==)

                 tot1=;

             else if (a==)

                 tot1++;

             else if (a==)

                 sum1+=tot1,tot1=;

             if (a==)

                 g=;

             else if (a==)

             {

                 v=b;

                 while (g> && f[g]<v)

                     g--,sum1++;

             }

             else if (a==)

             {

                 if (b<v)

                     sum1++;

                 else

                     f[++g]=b;

             }

         }

         printf("%d",sum1);

         return ;

     }