in c++ B: Write title lines for the functions that are called by the following main program. Do not supply the blocks for the functions (a)middle and (c)sum. Write the function definition of function (b)readIn and (d)largestCol. Use following main function for your program. int main() { double a[] = {1.1, 2.2, 3.3); int b[4][4] = {0}; a[0] = middle(a[0], a[1], a[1], a[2], a[2]); // (a) sets a[0] as the middle value (median of the parameter values) readIn(b, 4, 4); // (b) read in the entries of a 2-dimentional array with 4 rows and 4 columns from the user and save to parameter array b. b[3][3] = sum(b[1], 4, b[2][2]); // (c) adds elements from array and store it into b[3][3] int col_index = largestCol(b, 4, 4); // (d) col_index has the index of the column that contains the greatest column sum cout << "Largest column: " << endl; for (int r = 0; r < 4; r++) cout << b[r][col_index] << " "; cout << endl; return 0; } Sample input and output: 0 0 0 -1 1 1 3 4 1 1 1 1 2 4 3 2 Largest column: 0 3 1 3