Count Elements Smaller than or Equal to X in a Sorted Matrix in C++

We are given a matrix of size n x n, an integer variable x, and also, the elements in a matrix are placed in sorted order and the task is to calculate the count of those elements that are equal to or less than x.

Input −

matrix[3][3] = {{1, 2, 3}, {4, 5, 6}, {6, 7, 8}} and X = 4

Output −

count is 4

Explanation − we have to match our matrix data with the value x, so the elements less than or equals to x i.e. 4 are 1, 2, 3, 4. So the count is 4.

Input −

matrix[3][3] = {{1, 2, 3}, {4, 5, 6}, {6, 7, 8}} and X = 0

Output −

count is 0

Explanation − we have to match our matrix data with the value x, so there is no element that is less than or equals to x. So the count is 0.

Approach used in the below program is as follows

• Input the size of the matrix and then create the matrix of size nxn

• Start the loop, I from 0 to row size

• Inside the loop, I, start another loop j from 0 to column size

• Now, check if matrix[i][j] = x, IF yes then increase the count by 1 Else ignore the condition

• Return the total count

• Print the result.

Example

 Live Demo

#include <bits/stdc++.h>
using namespace std;
#define size 3
//function to count the total elements
int count(int matrix[size][size], int x){
   int count=0;
   //traversing the matrix row-wise
   for(int i = 0 ;i<size; i++){
      for (int j = 0; j<size ; j++){
         //check if value of matrix is less than or
         //equals to the x
         if(matrix[i][j]<= x){
            count++;
         }
      }
   }
   return count;
}
int main(){
   int matrix[size][size] ={
      {1, 2, 3},
      {4, 5, 6},
      {7, 8, 9}
   };
   int x = 5;
   cout<<"Count of elements smaller than or equal to x in a sorted matrix is: "<<count(matrix,x);
   return 0;
}

Output

If we run the above code we will get the following output −

Count of elements smaller than or equal to x in a sorted matrix is: 5