我正在尝试对数组的内容进行排序，虽然它似乎正在工作（没有运行时错误;正在执行排序任务），前10行虽然已排序但与其余行不一致
class coordSort.java
import java.io.*;
import java.util.Arrays;
import java.util.Scanner;
public class coordSort {
@SuppressWarnings({ "unchecked", "unused" })
public static void main (String args[]) throws IOException {
String xCoord, yCoord;
int coordSum;
Scanner input = new Scanner(System.in);
//Get x coordinate from user
System.out.print("Enter x coordinate: ");
xCoord = input.next();
//Get x coordinate from user
System.out.print("Enter y coordinate: ");
yCoord = input.next();
boolean sort = false;
char[] a = xCoord.toCharArray();
char[] b = yCoord.toCharArray();
//validate user input is a digit
if ( (Character.isDigit(a[0])) ) {
if(Character.isDigit(b[0]) ){
//digits entered - begin processing all coordinate values
sort = true;
}
}
//If validation failed, inform user
if(!sort){
System.out.println("Please enter a positive numeric value.");
}
if(sort){
//determine SUM of user entered coordinates
coordSum = Integer.parseInt(xCoord) + Integer.parseInt(yCoord);
//define coordinate array
String[][] coordUnsortedArray = new String[26][3];
int counter;
int commaCount;
String xCoordIn, yCoordIn;
int intXCoordIn, intYCoordIn, sumCoordIn, coordDiff;
//define input file
FileInputStream fileIn = new FileInputStream("coords.txt");
BufferedReader reader = new BufferedReader(new InputStreamReader(fileIn));
for (int j = 0; j < coordUnsortedArray.length; j++){
counter = 0;
commaCount = 0;
//line from file to variable
String coordSet = reader.readLine();
//look for the second "," to determine end of x coordinate
for(int k = 0; k < coordSet.length(); k++){
if (coordSet.charAt(k) == ',') {
commaCount++;
counter++;
if (commaCount == 2){
break;
}
}else{
counter++;
}
}
//define x coordinate
xCoordIn = (coordSet.substring(2,(counter - 1)));
intXCoordIn = Integer.parseInt(xCoordIn);
//define y coordinate
yCoordIn = (coordSet.substring((counter),coordSet.length()));
intYCoordIn = Integer.parseInt(yCoordIn);
//coordinate calculations
sumCoordIn = Integer.parseInt(xCoordIn) + Integer.parseInt(yCoordIn);
coordDiff = sumCoordIn - coordSum;
//load results to array
coordUnsortedArray[j][0] = xCoordIn;
coordUnsortedArray[j][1] = yCoordIn;
coordUnsortedArray[j][2] = Integer.toString(coordDiff);
//Output Array (BEFORE SORTING)
//System.out.println((j + 1) + ") " + coordUnsortedArray[j][0] + " : " + coordUnsortedArray[j][1] + " : " + coordUnsortedArray[j][2]);
}
System.out.println("\n");
fileIn.close();
String[][] coordsSorted = new String[26][3];
//Sort array coordDiff, column 3
Arrays.sort(coordUnsortedArray, new ColumnComparator(2));
//Print the sorted array
for(int i = 0; i < coordUnsortedArray.length; i++){
String[] row = coordUnsortedArray[i];
System.out.print((i + 1) + ") ");
for(int j = 0; j < row.length; j++) {
//System.out.print(row[j] + " | ");
coordsSorted[i][j] = row[j];
System.out.print(coordsSorted[i][j] + " : ");
}
System.out.print("\n");
}
}
}
}
class sortCoords.java -
import java.util.Comparator;
@SuppressWarnings("rawtypes")
class ColumnComparator implements Comparator {
int columnToSort;
ColumnComparator(int columnToSort) {
this.columnToSort = columnToSort;
}
//overriding compare method
public int compare(Object o1, Object o2) {
String[] row1 = (String[]) o1;
String[] row2 = (String[]) o2;
//compare the columns to sort
return row1[columnToSort].compareTo(row2[columnToSort]);
}
//overriding compare method
public int compare1(Object o1, Object o2) {
String[] row1 = (String[]) o1;
String[] row2 = (String[]) o2;
//compare the columns to sort
return row1[columnToSort].compareTo(row2[columnToSort]);
}
}
我试图通过第3列按数字顺序对数组进行排序。未排序的数组由包含以下内容的文本文件填充：
一个，44,67
B，31,49
C，93,6
我正在对用户输入进行数组计算，并按如下方式填充数组：
44,67,101
31,49,70
93,6,89
我希望sortedArray输出以下内容：
31,49,70
93,6,89
44,67,101
答案 0 :(得分：2)
这里有一个可能的混淆：
return row1[columnToSort].compareTo(row2[columnToSort])
这是一个字符串比较，而不是数字比较。如果你根据字符串进行排序，你会得到与数字不同的结果 - 即“1”，“10”，“100”，“9”vs 1,9,10,100
查看Integer.parseInt，如果您无法理解其余部分，请随时提出更多问题。
答案 1 :(得分：1)
正如spin_plate所说。你需要比较他们的int值，即你需要一个演员
int num1 = Integer.parseInt(row1[columnToSort]);
int num2 = Integer.parseInt(row2[columnToSort]);
if(num1 > num2)
return 1;
else
return 0;
将此代码放在compareTo方法中并检查。交换return语句以反向排序。
此外，在compareTo方法中添加一些错误检查将使代码更有效。
答案 2 :(得分：0)
好的，所以在这里提供的帮助之后，下面是我们找到的解决方案。再次感谢大家的帮助！希望下面的代码可以帮助其他人。
class1的代码 -
import java.io.*;
import java.util.Arrays;
import java.util.Scanner;
public class coordSort {
@SuppressWarnings({ "unchecked" })
public static void main (String args[]) throws IOException {
String xCoordChar, yCoordChar;
int xCoord, yCoord, coordSum;
Scanner input = new Scanner(System.in);
//Get x coordinate from user
System.out.print("Enter x coordinate: ");
xCoordChar = input.next();
//Get x coordinate from user
System.out.print("Enter y coordinate: ");
yCoordChar = input.next();
boolean sort = false;
char[] a = xCoordChar.toCharArray();
char[] b = yCoordChar.toCharArray();
//validate user input is a digit
if ( (Character.isDigit(a[0])) ) {
if(Character.isDigit(b[0]) ){
//digits entered - begin processing all coordinate values
sort = true;
}
}
//If validation failed, inform user
if(!sort){
System.out.println("Please enter a positive numeric value.");
}
if(sort){
//Parse user input characters to Integers
xCoord = Integer.parseInt(xCoordChar);
yCoord = Integer.parseInt(yCoordChar);
//determine SUM of user entered coordinates
coordSum = xCoord + yCoord;
//define coordinate array
int[][] coordUnsortedArray = new int[26][3];
int counter;
int commaCount;
String xCoordIn, yCoordIn;
int intXCoordIn, intYCoordIn, sumCoordIn, coordDiff;
//define input file
FileInputStream fileIn = new FileInputStream("coords.txt");
BufferedReader reader = new BufferedReader(new InputStreamReader (fileIn));
for (int j = 0; j < coordUnsortedArray.length; j++){
counter = 0;
commaCount = 0;
//line from file to variable
String coordSet = reader.readLine();
//look for the second "," to determine end of x coordinate
for(int k = 0; k < coordSet.length(); k++){
if (coordSet.charAt(k) == ',') {
commaCount++;
counter++;
if (commaCount == 2){
break;
}
}else{
counter++;
}
}
//define x coordinate
xCoordIn = (coordSet.substring(2,(counter - 1)));
intXCoordIn = Integer.parseInt(xCoordIn);
//define y coordinate
yCoordIn = (coordSet.substring((counter),coordSet.length()));
intYCoordIn = Integer.parseInt(yCoordIn);
//coordinate calculations
sumCoordIn = Integer.parseInt(xCoordIn) + Integer.parseInt (yCoordIn);
coordDiff = sumCoordIn - coordSum;
if (coordDiff < 0){
coordDiff = coordDiff * (-1);
}
//load results to array
coordUnsortedArray[j][0] = intXCoordIn;
coordUnsortedArray[j][1] = intYCoordIn;
coordUnsortedArray[j][2] = coordDiff;
}
fileIn.close();
System.out.print("\n");
System.out.println("Array Before Sorting:");
System.out.println("=====================");
//Array Before Sorting
for(int i = 0; i < coordUnsortedArray.length; i++){
int[] row = coordUnsortedArray[i];
System.out.print((i + 1) + ") ");
for(int j = 0; j < (row.length - 1); j++) {
coordUnsortedArray[i][j] = row[j];
if(j < 1){
System.out.print(coordUnsortedArray [i] [j] + ",");
}else{
System.out.println(coordUnsortedArray [i] [j]);
}
}
}
System.out.print("\n");
System.out.print("\n");
//Sort array coordDiff, column 3
Arrays.sort(coordUnsortedArray, new ColumnComparator(2));
System.out.println("Array After Sorting:");
System.out.println("====================");
//Original Array After Sorting
for(int i = 0; i < coordUnsortedArray.length; i++){
int[] row = coordUnsortedArray[i];
System.out.print((i + 1) + ") ");
for(int j = 0; j < (row.length - 1); j++) {
coordUnsortedArray[i][j] = row[j];
if(j < 1){
System.out.print(coordUnsortedArray[i][j] + ",");
}else{
System.out.println(coordUnsortedArray [i] [j]);
}
}
}
}
}
}
class2的代码 -
import java.util.Comparator;
@SuppressWarnings("rawtypes")
class ColumnComparator implements Comparator {
int columnToSort;
ColumnComparator(int columnToSort) {
this.columnToSort = columnToSort;
}
//Compare method
public int compare(Object o1, Object o2) {
int[] row1 = (int[]) o1;
int[] row2 = (int[]) o2;
int intRow1 = (row1[columnToSort]);
int intRow2 = (row2[columnToSort]);
return new Integer(intRow1).compareTo(new Integer(intRow2));
}
}