java辅导、java设计辅导讲解、讲解java报告、辅导ArrayLoopingExercise 辅导留学生 Statistics统计、回归、迭代

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package sampleProgram;

import java.util.Random;
/**
*
* @author
*/
public class ArrayLoopingExercise {

public static void arrayTesting(){

int [] intArray1 = {1, 2, 3};
int intArray2 [];
intArray2 = new int[4];
intArray2[0] = 4;
intArray2[1] = 5;
intArray2[3] = 7;

int a = intArray2[1];

int [][] iaa = {{1,2},{3, 4, 5}};
int [][] iaa2 = new int[2][3];
iaa2[0][0] = 5;
}

public static void loopConversion()
{
int a = 3, n = 6, result;
//We will use different loop to calculate result = a ^ n.
//Note that java has no exponent operator.

result = 1;
for (int i = 0; i < n; ++i)
{
result *= a;
}
System.out.println("for loop: result = " + result);

result = 1;
int j = 0;
while (j < n)
{
result *= a;
++j;
}
System.out.println("while loop: result = " + result);

result = 1;
int k = 0;
do
{
if (n == 0) break;

result *= a;
++k;

} while (k < n);
System.out.println("do/while loop: result = " + result);
}

public static void loopWithSorting()
{
int [] intArray = new int[20];

//Generate random numbers in the range [0, 99] to fill the array.
Random rand = new Random();
rand.setSeed(System.nanoTime());
for (int i = 0; i < intArray.length; ++ i)
{
intArray[i] = rand.nextInt(100);
}
//Print out the random array.
for (int i = 0; i < intArray.length; ++ i)
{
System.out.print (intArray[i] + ", ");
}
System.out.println();

//Sorting the array using bubble sort.
for (int i = 1; i < intArray.length; i++)
{
for (int j = intArray.length - 1; j >= i; j--)
{
if (intArray[j-1] > intArray[j])
{
int temp = intArray[j-1];
intArray [j-1] = intArray[j];
intArray [j] = temp;
}
}
}

//Print out the sorted array.
for (int i = 0; i < intArray.length; ++ i)
{
System.out.print (intArray[i] + ", ");
}
System.out.println();

}

public static void matrixMultiplication()
{
int [][] m1 = { {1, 2, 3},
{4, 5, 6} };

int [][] m2 = { {1, 2},
{3, 4},
{5, 6} };
int [][] mp = { {0, 0},
{0, 0} };

for (int i = 0; i < mp.length; ++i)
{
for (int j = 0; j < mp[i].length; ++j)
{
for (int k = 0; k < m1[0].length; ++k)
{
mp[i][j] += m1[i][k] * m2[k][j];
}
}
}

//Print out the matrix multiplication result.
for (int i = 0; i < mp.length; ++i)
{
for (int j = 0; j < mp[0].length; ++j)
{
System.out.print (mp[i][j] + ", ");
}
System.out.println();
}
}
}