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bytecodeman/PascalTriangle.java Secret

Last active Jul 10, 2020
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CSC-111 Two Dimensional Array Example
// (x+1)^0 1 1
// (x+1)^1 1 1 x + 1
// (x+1)^2 1 2 1 x^2 + 2x + 1
// (x+1)^3 1 3 3 1 x^3 + 3x^2 + 3x + 1
// (x+1)^4 1 4 6 4 1 x^4 + 4x^3 + 6x^2 + 4x + 1
// (x+1)^5 1 5 10 10 5 1 x^5 + 5x^4 + 10x^3 + 10x^2 = 5x + 1
// (x+1)^6 1 6 15 20 15 6 1 ...
// ...
public class PascalTriangle {
public static void main(String args[]) {
int pt[][] = new int[10][10];
generateTriangle(pt);
printTriangle(pt);
printXplus1Expansions(pt);
}
private static void generateTriangle(int x[][]) {
for (int row = 0; row < x.length; row++) {
x[row][0] = 1;
x[row][row] = 1;
for (int col = 1; col < row; col++)
x[row][col] = x[row-1][col-1] + x[row-1][col];
}
}
private static void printTriangle(int x[][]) {
for (int row = 0; row < x.length; row++) {
for (int col = 0; col <= row; col++)
System.out.printf("%6d", x[row][col]);
System.out.println();
}
}
private static void printXplus1Expansions(final int x[][]) {
if (x == null || x.length == 0)
return;
for (int row = 0; row < x.length; row++) {
if (row == 0) {
System.out.printf("1");
System.out.println();
}
else if (row == 1) {
System.out.printf("x + 1");
System.out.println();
}
else {
System.out.printf("x^%d", row);
for (int col = 1; col < row; col++) {
if (col == row - 1) {
System.out.printf(" + %dx", x[row][col]);
}
else {
System.out.printf(" + %dx^%d", x[row][col], row - col);
}
}
System.out.printf(" + %d", 1);
System.out.println();
}
}
}
}
public class PascalTriangle2 {
public static void main(String args[]) {
int pt[][] = generateTriangle();
printTriangle(pt);
}
// i -> array
// 0 -> [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
// 1 -> [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
// 2 -> [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
// 3 -> [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
// 4 -> [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
// 5 -> [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
// ...
private static int[][] generateTriangle() {
int x[][] = new int[10][10];
for (int row = 0; row < x.length; row++) {
x[row][0] = 1;
x[row][row] = 1;
for (int col = 1; col < row; col++)
x[row][col] = x[row-1][col-1] + x[row-1][col];
}
return x;
}
private static void printTriangle(int x[][]) {
for (int row = 0; row < x.length; row++) {
for (int col = 0; col <= row; col++)
System.out.printf("%6d", x[row][col]);
System.out.println();
}
}
}
public class PascalTriangle3 {
public static void main(String args[]) {
var pt = initStructure(10);
generateTriangle(pt);
printTriangle(pt);
}
// i -> array
// 0 -> [0]
// 1 -> [0, 0]
// 2 -> [0, 0, 0]
// 3 -> [0, 0, 0, 0]
// 4 -> [0, 0, 0, 0, 0]
// 5 -> [0, 0, 0, 0, 0, 0]
// ...
private static int[][] initStructure(final int size) {
var x = new int[size][];
for (int i = 0; i < size; i++)
x[i] = new int[i+1];
return x;
}
private static void generateTriangle(final int x[][]) {
for (int row = 0; row < x.length; row++) {
x[row][0] = 1;
x[row][row] = 1;
for (int col = 1; col < row; col++)
x[row][col] = x[row-1][col-1] + x[row-1][col];
}
}
private static void printTriangle(final int x[][]) {
for (int row = 0; row < x.length; row++) {
for (int col = 0; col <= row; col++)
System.out.printf("%6d", x[row][col]);
System.out.println();
}
}
}
public class TwoDArrayExample {
private static int[][] initMatrix(int numRows, int numCols) {
int x[][] = new int[numRows][numCols];
for (int i = 0; i < x.length; i++)
for (int j = 0; j < x[i].length; j++)
x[i][j] = (int) (100 * Math.random()) + 1;
return x;
}
private static void printMatrix(int[][] x) {
for (int i = 0; i < x.length; i++) {
for (int j = 0; j < x[i].length; j++)
System.out.printf("%5d", x[i][j]);
System.out.println();
}
}
private static int biggest(int numbs[][]) {
int largest = numbs[0][0];
for (int i = 0; i < numbs.length; i++)
for (int j = 0; j < numbs[i].length; j++)
if (numbs[i][j] > largest)
largest = numbs[i][j];
return largest;
}
public static void main(String args[]) {
int x[][] = initMatrix(10, 8);
printMatrix(x);
System.out.printf("Biggest Number in Array = %d\n", biggest(x));
}
}
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