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  1. [20pts] Assume the following delcarations and fill in the table with either the type of the given expression, or "error" if appropriate. 
    
double x;
string s;
double* A;
int** M;
string** W;
    expressiontype
    x
    s
    A
    M
    W
    x[0]
    s[0]
    A[0]
    M[0]
    W[0]
    expressiontype
    x[0][0]
    s[0][0]
    A[0][0]
    M[0][0]
    W[0][0]
    x[0][0][0]
    s[0][0][0]
    A[0][0][0]
    M[0][0][0]
    W[0][0][0]
  2. [5pts] Consider the following function prototype. 
    
/* 
Finds the column (and the sum of the entries in that column) 
such that its sum is the largest in all columns. 

A: 2D array
rows, cols: #rows and #columns in the array
pCol: points to an object to hold the index of the max column
pSum: points to an object to hold the sum of the max column
*/
void findMaxSum(double** A, int rows, int cols, int* pCol, double* pSum);
    The code snippet below shows the main function. Fill in the blank with the correct function call to findMaxSum. Assume variables Arr, n, m have been set correctly. 
    
double** Arr;  // 2D array 
int n;        // # rows
int m;        // # cols


int col; 
double sum;

// Give the correct function call to findMaxSum() below:


--------------------------------------------------------------

cout << "Column " << col << " has the maximum sum with " << sum << endl;
  3. [75pts] Write a program hw.cpp that works as follows: 

    ~/$ ./hw
What size? 2 x 3 
1 8 0
4 7 7 
rows: 0 1 
cols: 1

    In particular:

    1. The program asks the user to specify a size n x m of a matrix of integers.
    2. It reads in n x m numbers.
    3. It prints out the indices of rows and columns such that the sum of numbers in that row or column is a multiple of 3.
    For the above run, Therefore, both of rows 0 and 1 are listed in the output. Therefore, only column 1 is listed in the output.

    Here are some more example runs. Your program must read input and produce output with the exact same formatting! The red text represents the user input. 

    ~/$ ./hw
What size? 1 x 1
6
rows: 0 
cols: 0 

    ~/$ ./hw
What size? 1 x 1
5
rows:
cols:

    ~/$ ./hw
What size? 3 x 3 
6 9 5
4 6 8
9 4 14
rows: 1 2 
cols: 2 

    ~/$ ./hw
What size? 5 x 3
3 4 1 
6 2 3
2 4 5
1 3 2
3 2 4
rows: 3 4 
cols: 0 1 2

    ~/$ ./hw
What size? 3 x 5
3 6 2 1 3 
4 2 4 3 2 
1 3 5 2 4 
rows: 0 1 2 
cols: 3 4

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