#include <iostream>
#include <map>
#include <bitset>
using namespace std;
map<int, int> fr;
int main() {
bitset<1000010> fr;
bitset<1000010> db;
int x, nr = 0;
while(cin >> x) {
if(fr[x]) db[x] = 1;
fr[x] = 1;
}
for (int i = 1; i <= 1000000; i++) {
if(fr[i] && !db[i])
nr++;
}
cout << nr;
}
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