#백준_1592 영식이와 친구들 - Java 자바

# 유형 : 시뮬레이션

package bj;
 
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;
 
public class p1592 {
    static int N,M,L;
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());
        N = Integer.parseInt(st.nextToken());
        M = Integer.parseInt(st.nextToken());
        L = Integer.parseInt(st.nextToken());
    
        int arr[] = new int[N];
        int cnt=0;
        int index=0;
        while(true) {
            arr[index]++;
            if(arr[index] == M)
                break;
            
            if(arr[index]%2 == 0) {
                if(index + L >= N) {
                    index = L-N+index;
                }else {
                    index+=L;
                }
            }else if(arr[index]%2 ==1){
                if(index-L<0) {
                    index = N-L+index;
                }else
                    index-=L;
            }
            cnt++;
        }
        System.out.println(cnt);
    }
}