Code Snippet - Summed Area Table

SUMMED AREA TABLE
Using the method described here, I have written the following code to calculate a summed area table. A sample image table of 5x5 dimensions has been assumed for simplicity. The code snippet and its results are given below.

CODE
// assumed height and width of the input table
#define height 6
#define width 6

// input matrix - 5x5
long matrix[ height - 1][width -1] = {{5,2,3,4,1},{1,5,4,2,3},{2,2,1,3,4},{3,5,6,4,5},{4,1,3,2,6}};
// output matrix - 6x6
long sat[height][width];

void sat_matrix(){
 // formula variables
      int a=0, b=0, c=0, m=0;
      // matrix traversal loop for calculating the SAT
for(int i = 0; i < height; i++){
for(int j = 0; j < width; j++){
                     // following code picks up array elements within bounds and picks "zero"
                     // for values outside bounds.
a = (i-1>=0)?sat[i-1][j]:0;
b = (j-1>=0)?sat[i][j-1]:0;
c = ((i-1>=0)&&(j-1>=0))?sat[i-1][j-1]:0;
m = ((i-1>=0)&&(j-1>=0))?matrix[i-1][j-1]:0;
                      // ACTUAL FORMULA FOR SUMMED AREA TABLE
sat[i][j] = m + a + b - c;
}
}
}

PROCEDURE:
Use the function as it is and write supporting code. The code written was compiled using g++ compiler in cygwin environment

OUTPUT: