edu.princeton.cs.algs4.StdArrayIO Maven / Gradle / Ivy
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/******************************************************************************
* Compilation: javac StdArrayIO.java
* Execution: java StdArrayIO < input.txt
* Dependencies: StdOut.java
* Data files: https://introcs.cs.princeton.edu/java/22library/tinyDouble1D.txt
* https://introcs.cs.princeton.edu/java/22library/tinyDouble2D.txt
* https://introcs.cs.princeton.edu/java/22library/tinyBoolean2D.txt
*
* A library for reading in 1D and 2D arrays of integers, doubles,
* and booleans from standard input and printing them out to
* standard output.
*
* % more tinyDouble1D.txt
* 4
* .000 .246 .222 -.032
*
* % more tinyDouble2D.txt
* 4 3
* .000 .270 .000
* .246 .224 -.036
* .222 .176 .0893
* -.032 .739 .270
*
* % more tinyBoolean2D.txt
* 4 3
* 1 1 0
* 0 0 0
* 0 1 1
* 1 1 1
*
* % cat tinyDouble1D.txt tinyDouble2D.txt tinyBoolean2D.txt | java StdArrayIO
* 4
* 0.00000 0.24600 0.22200 -0.03200
*
* 4 3
* 0.00000 0.27000 0.00000
* 0.24600 0.22400 -0.03600
* 0.22200 0.17600 0.08930
* 0.03200 0.73900 0.27000
*
* 4 3
* 1 1 0
* 0 0 0
* 0 1 1
* 1 1 1
*
******************************************************************************/
package edu.princeton.cs.algs4;
/**
* Standard array IO. This class provides methods for reading
* in 1D and 2D arrays from standard input and printing out to
* standard output.
*
* For additional documentation, see
* Section 2.2 of
* Computer Science: An Interdisciplinary Approach
* by Robert Sedgewick and Kevin Wayne.
*
* @author Robert Sedgewick
* @author Kevin Wayne
*/
public class StdArrayIO {
// it doesn't make sense to instantiate this class
private StdArrayIO() { }
/**
* Reads a 1D array of doubles from standard input and returns it.
*
* @return the 1D array of doubles
*/
public static double[] readDouble1D() {
int n = StdIn.readInt();
double[] a = new double[n];
for (int i = 0; i < n; i++) {
a[i] = StdIn.readDouble();
}
return a;
}
/**
* Prints an array of doubles to standard output.
*
* @param a the 1D array of doubles
*/
public static void print(double[] a) {
int n = a.length;
StdOut.println(n);
for (int i = 0; i < n; i++) {
StdOut.printf("%9.5f ", a[i]);
}
StdOut.println();
}
/**
* Reads a 2D array of doubles from standard input and returns it.
*
* @return the 2D array of doubles
*/
public static double[][] readDouble2D() {
int m = StdIn.readInt();
int n = StdIn.readInt();
double[][] a = new double[m][n];
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
a[i][j] = StdIn.readDouble();
}
}
return a;
}
/**
* Prints the 2D array of doubles to standard output.
*
* @param a the 2D array of doubles
*/
public static void print(double[][] a) {
int m = a.length;
int n = a[0].length;
StdOut.println(m + " " + n);
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
StdOut.printf("%9.5f ", a[i][j]);
}
StdOut.println();
}
}
/**
* Reads a 1D array of integers from standard input and returns it.
*
* @return the 1D array of integers
*/
public static int[] readInt1D() {
int n = StdIn.readInt();
int[] a = new int[n];
for (int i = 0; i < n; i++) {
a[i] = StdIn.readInt();
}
return a;
}
/**
* Prints an array of integers to standard output.
*
* @param a the 1D array of integers
*/
public static void print(int[] a) {
int n = a.length;
StdOut.println(n);
for (int i = 0; i < n; i++) {
StdOut.printf("%9d ", a[i]);
}
StdOut.println();
}
/**
* Reads a 2D array of integers from standard input and returns it.
*
* @return the 2D array of integers
*/
public static int[][] readInt2D() {
int m = StdIn.readInt();
int n = StdIn.readInt();
int[][] a = new int[m][n];
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
a[i][j] = StdIn.readInt();
}
}
return a;
}
/**
* Print a 2D array of integers to standard output.
*
* @param a the 2D array of integers
*/
public static void print(int[][] a) {
int m = a.length;
int n = a[0].length;
StdOut.println(m + " " + n);
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
StdOut.printf("%9d ", a[i][j]);
}
StdOut.println();
}
}
/**
* Reads a 1D array of booleans from standard input and returns it.
*
* @return the 1D array of booleans
*/
public static boolean[] readBoolean1D() {
int n = StdIn.readInt();
boolean[] a = new boolean[n];
for (int i = 0; i < n; i++) {
a[i] = StdIn.readBoolean();
}
return a;
}
/**
* Prints a 1D array of booleans to standard output.
*
* @param a the 1D array of booleans
*/
public static void print(boolean[] a) {
int n = a.length;
StdOut.println(n);
for (int i = 0; i < n; i++) {
if (a[i]) StdOut.print("1 ");
else StdOut.print("0 ");
}
StdOut.println();
}
/**
* Reads a 2D array of booleans from standard input and returns it.
*
* @return the 2D array of booleans
*/
public static boolean[][] readBoolean2D() {
int m = StdIn.readInt();
int n = StdIn.readInt();
boolean[][] a = new boolean[m][n];
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
a[i][j] = StdIn.readBoolean();
}
}
return a;
}
/**
* Prints a 2D array of booleans to standard output.
*
* @param a the 2D array of booleans
*/
public static void print(boolean[][] a) {
int m = a.length;
int n = a[0].length;
StdOut.println(m + " " + n);
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
if (a[i][j]) StdOut.print("1 ");
else StdOut.print("0 ");
}
StdOut.println();
}
}
/**
* Unit tests {@code StdArrayIO}.
*
* @param args the command-line arguments
*/
public static void main(String[] args) {
// read and print an array of doubles
double[] a = StdArrayIO.readDouble1D();
StdArrayIO.print(a);
StdOut.println();
// read and print a matrix of doubles
double[][] b = StdArrayIO.readDouble2D();
StdArrayIO.print(b);
StdOut.println();
// read and print a matrix of doubles
boolean[][] d = StdArrayIO.readBoolean2D();
StdArrayIO.print(d);
StdOut.println();
}
}
/******************************************************************************
* Copyright 2002-2018, Robert Sedgewick and Kevin Wayne.
*
* This file is part of algs4.jar, which accompanies the textbook
*
* Algorithms, 4th edition by Robert Sedgewick and Kevin Wayne,
* Addison-Wesley Professional, 2011, ISBN 0-321-57351-X.
* http://algs4.cs.princeton.edu
*
*
* algs4.jar is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* algs4.jar is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with algs4.jar. If not, see http://www.gnu.org/licenses.
******************************************************************************/