I have working code that finds the maximum sum of elements within a sub-rectangle of a 2D array. I’m wondering if there are any optimization techniques I could use to improve its performance.

The input is

1. field: 2D Array
2. fieldRow: size of array in X dimension
3. fieldCol: size of array in Y dimension
4. window_size: The size of window

The output

• the maximum sum of elements within a sub-rectangle

#include <stdio.h>
#include <limits.h>
#include <stdlib.h>
//TODO if max_sum already found in this windows size
int main()
{   int max_sum = INT_MIN;
    int loopCount = 0; // for performance checking

    //INPUT for 2D array field
    int field[4][5] = {
        {0, -5, 3, 4, 9},
        {10, 21, 18, -11, 0},
        {0, -2, 5, 9, 11},
        {12, 7, 8, 3, -1}};

    int fieldCol = 5; // INPUT for Y dimension of field
    int fieldRow = 4; // INPUT for X simension of field
    int window_size = 6; // INPUT for the maximum area of subrectangle

    //output 0 and exit program for window_size 0
    if (window_size <= 0)
    {
        printf("0");
        exit(0);
    }

    // incase of window_size larger than area of field
    int max_area = (fieldCol * fieldRow);
    if (window_size > max_area)
    {
        window_size = max_area;
    }

    for (int X = 0; X < fieldRow; X++) // start position of x
    {
        for (int Y = 0; Y < fieldCol; Y++) // start position of y
        {
            for (int x = X; x < fieldRow; x++) // end position of x
            {
                for (int y = Y; y < fieldCol; y++) // end position of y
                {
                    int sum = 0;
                    int count = 0;
                    //sum of all elements from starting(X,Y) to ending(x,y) position
                    for (int c_x = X; c_x <= x; c_x++)
                    {
                        for (int c_y = Y; c_y <= y; c_y++)
                        {
                            loopCount++; //benchmarking
                            sum += field[c_x][c_y];
                            count++; //count for subrectangle area
                            if(count>window_size){
                                break;
                            }
                        }
                    }

                    //set max_sum incase of the area of subrectangle is lower or equal to window_size
                    if (sum > max_sum && count <= window_size)
                    {
                        max_sum = sum;
                    }
                }
            }
        }
    }

    printf("%d", max_sum);
    printf("nloop count %d", loopCount);

    return 0;
}