p11660.java

/*
	DP와 구간합을 활용하여야 한다.
	사각형의 테두리 안을 구하려면
	좌상 꼭짓점:(x1, y1) , 우하 꼭짓점:(x2, y2) 일때 구간 합은 다음과 같다
	DP[i][j] =  DP[x2][y2] - DP[x1-1][y2] - DP[x2][y1-1] + DP[x1-1][y1-1];
*/
import java.io.*;
import java.util.*;
public class p11660 {
    static int n, m, board[][], sum[][];
    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());
        board = new int[n + 1][n + 1];
        sum = new int[n + 1][n + 1];
        for (int i = 1; i <= n; i++) {
            st = new StringTokenizer(br.readLine());
            for (int j = 1; j <= n; j++) {
                board[i][j] = Integer.parseInt(st.nextToken());
            }
        }
        
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= n; j++) {
                sum[i][j] = sum[i][j - 1] + sum[i - 1][j] - sum[i - 1][j - 1] + board[i][j];
            }
        }
        
        for (int i = 0; i < m; i++) {
            st = new StringTokenizer(br.readLine());
            int x1 = Integer.parseInt(st.nextToken());
            int y1 = Integer.parseInt(st.nextToken());
            int x2 = Integer.parseInt(st.nextToken());
            int y2 = Integer.parseInt(st.nextToken());
            int result = prefixSum(x1, y1, x2, y2);
            System.out.println(result);
        }
    }
    static int prefixSum(int x1, int y1, int x2, int y2) {
        return sum[x2][y2] - sum[x2][y1 - 1] - sum[x1 - 1][y2] + sum[x1 - 1][y1 - 1];
    }
}