[BOJ] 백준 2457 공주님의 정원

[문제]

https://www.acmicpc.net/problem/2847

 

 

[소스 코드]

import java.io.*;
import java.util.*;
public class Main {
    public static void main(String[] args) throws IOException {
    	BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    	int n = Integer.parseInt(br.readLine());
    	int[] level = new int[n];
    	for(int i=0;i<n;i++) {
    		level[i] = Integer.parseInt(br.readLine());
    	}
    	int result = 0;
    	for(int i=n-1;i>0;i--) {
    		if(level[i-1] >= level[i]) {
    			int diff = level[i-1] - level[i] +1;
    			result += diff;
    			level[i-1] -= diff;
    		}
    	}
    	System.out.println(result);
    }
}