곱셈

https://www.acmicpc.net/problem/1629

1629번: 곱셈

// 자바

import java.util.*;
import java.io.*;
 
public class Main{
  public static long getResult(long A, long B, long C) {
    if(B == 1) 
      return A%C;
    else {
      long temp = getResult(A, B/2, C);
      if(B%2 == 0) return (temp * temp) % C;
      else return ((temp * temp % C) * A % C) % C;
    }
      
  }
  
  public static void main(String[] args) throws Exception {
 
    // Please Enter Your Code Here
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer(br.readLine());
    
    long A = Long.parseLong(st.nextToken());
    long B = Long.parseLong(st.nextToken());
    long C = Long.parseLong(st.nextToken()); 
     
    System.out.println(getResult(A, B, C));
  }
}

 

// 개념에 대한 참조

https://st-lab.tistory.com/237