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

typedef struct Node {
    char name[50];
    struct Node *next;
} Node;

int main() {
    int total, cap, pos;
    if (scanf("%d %d %d", &total, &cap, &pos) != 3) {
        printf("Invalid input\n");
        return 0;
    }
    if (total < 10 || total > 200 || cap < 1 || cap > 20 || pos < 1 || pos > total) {
        printf("Invalid input\n");
        return 0;
    }

    Node *head = NULL, *tail = NULL;
    for (int i = 0; i < total; i++) {
        Node newNode = (Node)malloc(sizeof(Node));
        if (scanf("%s", newNode->name) != 1) {
            printf("Invalid input\n");
            return 0;
        }
        newNode->next = NULL;
        if (head == NULL) {
            head = tail = newNode;
        } else {
            tail->next = newNode;
            tail = newNode;
        }
    }

    // Compute how many rounds until position 'pos'
    int round = (pos - 1) / cap + 1;
    printf("%d\n", round);

    // Free memory
    Node *temp;
    while (head) {
        temp = head;
        head = head->next;
        free(temp);
    }
    return 0;
}