Count pairs sum in matrices

package gfg;

//Count pairs sum in matrices

import java.io.*;
import java.util.*;

class GFG {
  public static void main(String args[]) throws IOException {
      BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
      int t = Integer.parseInt(read.readLine());
      
      while (t-- > 0) {
          String input[] = read.readLine().split(" ");
          
          int n = Integer.parseInt(input[0]);
          int x = Integer.parseInt(input[1]);
          
          int mat1[][] = new int[n][n];
          
          for(int i = 0;i<n;i++){
              input = read.readLine().split(" ");
              
              for(int j = 0;j<n;j++){
                  mat1[i][j] = Integer.parseInt(input[j]);
              }
          }
          
          int mat2[][] = new int[n][n];
          
          for(int i = 0;i<n;i++){
              input = read.readLine().split(" ");
              
              for(int j = 0;j<n;j++){
                  mat2[i][j] = Integer.parseInt(input[j]);
              }
          }
          
      
          
          Solution ob = new Solution();
          System.out.println(ob.countPairs(mat1,mat2,n,x));
      }
  }
}

class Solution {
  int countPairs(int mat1[][], int mat2[][], int n, int x) {
      // code here
      int r1 = 0;
      int c1 = 0;
      int r2 = n - 1;
      int c2 = n - 1;
      int count = 0;
      
      while(r1 < n && r2 >= 0) {
          int sum = mat1[r1][c1] + mat2[r2][c2];
          
          if(sum == x) {
              count++;
              c1++;
              c2--;
          }
          
          if(sum > x) {
              c2--;
          }
          
          if(sum < x) {
              c1++;
          }
          
          if(c1 == n) {
              c1 = 0;
              r1++;
          }
          
          if(c2 == -1) {
              c2 = n - 1;
              r2--;
          }
      }
      
      return count;
  }
}