ABC022B - Bumble Bee

問題：B - Bumble Bee

#include <cstdio>
#include <iostream>
#include <set>
using namespace std;

#define REP(i, n) for(int i = 0; i < (n); ++i)

int main(void) {
    int n, a;
    set<int> se;

    scanf ("%d", &n);
    REP(i, n) {
        scanf ("%d", &a);
        se.insert(a);
    }

    printf ("%d\n", n - (int)se.size());
    return 0;
}