function calculate_sum(arr) { var sum = []; for(x=0; x<4; x++) { for(j=0; j<4; j++) { sum.push(arr[x][j] + arr[x][j+1] + arr[x][j+2] + arr[x+1][j+1] + arr[x+2][j] + arr[x+2][j+1] + arr[x+2][j+2]); }; }; return Math.max.apply(null, sum); }