2D and tally arrays

These are from 25 November.

twodimensional.cpp

// two-dimensional arrays

#include <iostream>
#include <cstdlib>
using namespace std;

const int ROWS = 6;
const int COLS = 7;

void print_board(char board[ROWS][COLS]);

int main()
{
    srand(time(NULL)); // Initialize random
    char board[ROWS][COLS];
    // Initialize the board
    for(int r = 0; r < ROWS; r++)
    {
        for(int c = 0; c < COLS; c++)
        {
            //cout << r << ", " << c << "\n";
            board[r][c] = '.';
        }
    }
    // PRint the board
    print_board(board);
    // Place random letters on the board
    for(char letter = 'A'; letter <= 'Z'; letter++)
    {
        // Choose random location on the board
        int r = rand() % ROWS;
        int c = rand() % COLS;
        while(board[r][c] != '.')
        {
            r = rand() % ROWS;
            c = rand() % COLS;
        }
        board[r][c] = letter;
        //cout << r << "," << c << "\n";
    }
    cout << "AFTER:\n";
    print_board(board);
    return 0;
}


void print_board(char board[ROWS][COLS])
{
   for(int r = 0; r < ROWS; r++)
    {
        for(int c = 0; c < COLS; c++)
        {
            cout << board[r][c];
        }
        cout << "\n";
    }
 }

frequency.cpp

#include <iostream>
using namespace std;
const int NUM_LETTERS = 26;

int main()
{
    string mesg =
        "Hello WORLD, this IS A test Message.";
    int tally[NUM_LETTERS] = { 0 };

    for(int i = 0; i < mesg.length(); i++)
    {
        char c = mesg[i];
        if(c >= 'A' && c <= 'Z') {
            int j = c - 'A';
            tally[j]++;
        }
        else if(c >= 'a' && c <= 'z') {
            int j = c - 'a';
            tally[j]++;
        }
    }
    // print results
    for(int i = 0; i < NUM_LETTERS; i++) {
        char c = 'A' + i;
        cout << c << ": " << tally[i] << "\n";
    }
}

dice.cpp

#include <iostream>
#include <cstdlib>
using namespace std;
int main()
{
    srand(time(NULL));
    int tally[13] = { 0 }; // Only need 2-12.
    const int NUM_ROLLS = 10000;
    for(int i = 0; i < NUM_ROLLS; i++)
    {
        int d1 = rand() % 6 + 1;
        int d2 = rand() % 6 + 1;
        int k = d1+d2;
        tally[k]++;
    }
    for(int i = 2; i <= 12; i++)
    {
        if(i < 10) cout << " ";
        cout << i << ": ";
        for(int j = 0; j < tally[i]/40; j++)
        {
            cout << "=";
        }
        cout << "\n";
    }
    return 0;
}