#include <stdio.h>
#include <stdlib.h>

int main() {
    int *ind, *array, n, i, ans, temp, j;
    while (1) {
        if (scanf("%d", &n) != 1) break;
        ind = malloc(sizeof(int)*(n + 1));
        array = malloc(sizeof(int)*(n + 1));
        for (i = 1; i <= n; i++) {
            scanf("%d", (array + i));
            ind[array[i]] = i;
        }
        ans = 0;
        for (i = 1; i <= n; i++) {
            if (ind[i] == i)
                continue;
            temp = array[i];
            array[i] = array[ind[i]];
            array[ind[i]] = temp;
            ind[temp] = ind[i];
            ind[i] = i;
            ans++;
        }
        printf("%d\n", ans);
    }
    return 0;
}