#include <bits/stdc++.h>
using namespace std;
int main(){
int a, b = 0, c = 0, d = 1, e = 0, f;
cin >> a;
do{
if(a != 0 && b == 0){
if(c != a && e == 0){
d++;
}
else{
e++;
}
c = a;
}
else{
b++;
}
}while(cin >> a);
cout << d;
return 0;
}
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