// editor3#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Node {
    char name[20];
    struct Node* next;
};
int main() {
    int total_people, capacity, asker_pos;
    char names[200][20];
    int i;
    if (scanf("%d %d %d", &total_people, &capacity, &asker_pos) != 3) {
        printf("Invalid input\n");
        return 1;
    }
    if (total_people < 10 || total_people > 200) {
        printf("Invalid input\n");
        return 1;
    }
    if (capacity < 1 || capacity > 20) {
        printf("Invalid input\n");
        return 1;
    }
    if (asker_pos < 1 || asker_pos > total_people) {
        printf("Invalid input\n");
        return 1;
    }
    for (i = 0; i < total_people; i++) {
        scanf("%s", names[i]);
    }
    int rounds = (asker_pos - 1) / capacity + 1;
    printf("%d\n", rounds);
    return 0;
}