source_code: import java.io.*;
  import java.util.*;
  public class Codechef{
  	
  
      public static void main(String []args){
      			Scanner in = new Scanner(System.in);
  
      long n=in.nextLong();
  		long m=in.nextLong();
  		long k=in.nextLong();
  		long l=in.nextLong();
   
  		long j=((k+l)/m);
  		if((k+l)%m!=0)j++;
  		if((k+l>n) || j*m>n) {
  			System.out.println(-1);
  		}else {
  			
  			System.out.println(j);
  		}
  
  
      }
  
  }