Create Random Numbers exercise

This is just the first part of the RowsCols exercise.
I thought it'd be better to split them up to make
them more manageable.

Author: phrdang

src/com/codefortomorrow/intermediate/chapter10/practice/RandomNumbers.java

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+package com.codefortomorrow.intermediate.chapter10.practice;
+
+/*
+Random Numbers
+
+Fill a 4 x 6 integer array with 24 random values from 7 to 77.
+Use the randInt(min, max) method that is given to you to do this.
+To call the method, type randInt(7, 77) and assign it to
+an array element. For example: list[0][0] = randInt(7, 77);
+
+Print the values in 4 rows of 6 elements.
+Keep track of the sum of all the values in the array.
+Display the sum on its own line under the array values.
+Keep track of the maximum and minimum value in the array.
+Display the max and min below the sum.
+
+Hint: You will need to set the max to Integer.MIN_VALUE
+and min to Integer.MAX_VALUE when you first initialize them.
+This ensures that when you iterate through the
+randomly generated numbers in your array, the max and min
+are updated correctly.
+(You can also set max to 6 and min to 78.)
+*/
+
+public class RandomNumbers {
+    public static void main(String[] args) {
+        // write code here
+    }
+
+    /**
+	 * Returns a random integer
+	 * in the range [min, max]
+	 * @param min  minimum random integer
+	 * @param max  maximum random integer
+	 * @return a random integer in the range
+	 * [min, max]
+	 */
+	public static int randInt(int min, int max) {
+		return min + (int) (Math.random() * ((max - min) + 1));
+	}
+}

src/com/codefortomorrow/intermediate/chapter10/solutions/RandomNumbers.java

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+package com.codefortomorrow.intermediate.chapter10.solutions;
+
+/*
+Random Numbers
+
+Fill a 4 x 6 integer array with 24 random values from 7 to 77.
+Use the randInt(min, max) method that is given to you to do this.
+To call the method, type randInt(7, 77) and assign it to
+an array element. For example: list[0][0] = randInt(7, 77);
+
+Print the values in 4 rows of 6 elements.
+Keep track of the sum of all the values in the array.
+Display the sum on its own line under the array values.
+Keep track of the maximum and minimum value in the array.
+Display the max and min below the sum.
+
+Hint: You will need to set the max to Integer.MIN_VALUE
+and min to Integer.MAX_VALUE when you first initialize them.
+This ensures that when you iterate through the
+randomly generated numbers in your array, the max and min
+are updated correctly.
+(You can also set max to 6 and min to 78.)
+*/
+
+public class RandomNumbers {
+    public static void main(String[] args) {
+        int[][] a = new int[4][6]; // create 4x6 array
+		int sum = 0; // sum of all elements in array
+		int max = Integer.MIN_VALUE; // max element in array
+		int min = Integer.MAX_VALUE; // min element in array
+
+		// iterate through each element in a
+		for (int row = 0; row < 4; row++) {
+			for (int col = 0; col < 6; col++) {
+				// generate a random number from 7 to 77
+				// and store it in the array
+				a[row][col] = randInt(7, 77);
+
+				// print that element
+				System.out.print(a[row][col] + "\t");
+
+				// keep a running total of all elements
+				sum += a[row][col];
+
+				// update min or max as needed
+				if (a[row][col] < min) {
+					min = a[row][col];
+				}
+					
+				if (a[row][col] > max) {
+					max = a[row][col];
+				}
+			}
+			System.out.println(); // move to next row
+		}
+
+		// display the sum of all elements
+		// and the max and min element
+		System.out.println("Sum: " + sum);
+		System.out.println("Max: " + max);
+		System.out.println("Min: " + min);
+    }
+
+    /**
+	 * Returns a random integer
+	 * in the range [min, max]
+	 * @param min  minimum random integer
+	 * @param max  maximum random integer
+	 * @return a random integer in the range
+	 * [min, max]
+	 */
+	public static int randInt(int min, int max) {
+		return min + (int) (Math.random() * ((max - min) + 1));
+	}
+}