在数组中排序字符串时遇到了麻烦。
我应该从我的代码中获得两个不同的输出,但我只能按升序获得输出。
import java.util.*;
public class nextLineArray1
{
public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
String names[]=new String[12];
System.out.println("Enter the 12 names: ");
//Load Array
for(int i = 0; i < 12; i++)
{
names[i] = input.nextLine();
}
//Print descending order list
String[] descSort;
descSort=bubbleSortDesc(names);
System.out.println("Names listed sorted in descending order (via BubbleSort): ");
for(int x=0; x < names.length; x++)
{
System.out.println(names[x]);
}
//Print ascending order list
String[] ascSort;
ascSort=bubbleSortAsc(names);
System.out.println("Names listed sorted in ascending order (via BubbleSort): ");
for(int z=0; z < names.length; z++)
{
System.out.println(names[z]);
}
}
public static String[] bubbleSortDesc(String[] names)
{
String temp;
int passNum, i, result;
for(passNum=1; passNum <= 11; passNum++)
{
for(i = 0; i<=(11-passNum); i++)
{
result=names[i].compareToIgnoreCase(names[i+1]);
if(result>0)
{
temp=names[i];
names[i]=names[i+1];
names[i+1]=temp;
}
}
}
return names;
}
public static String[] bubbleSortAsc(String[] names)
{
String temp;
int passNum, i, result;
for(passNum=1; passNum <= 11; passNum++)
{
for(i = 0; i<=(11-passNum); i++)
{
result=names[i].compareToIgnoreCase(names[i]);
if(result>0)
{
temp=names[i-1];
names[i-1]=names[i];
names[i]=temp;
}
}
}
return names;
}
}
解释为什么它只按升序排序,将会更有帮助。
提前致谢。
答案 0 :(得分:1)
我认为bubbleSortDesc
按升序排序,而BubbleSortAsc
根本不起作用:
//In BubbleSortAsc
result=names[i].compareToIgnoreCase(names[i]);
//result == 0, since names[i] is definitely equal to names[i]
if(result>0)
{
//Never reached
temp=names[i-1];
names[i-1]=names[i];
names[i]=temp;
}
所以,你应该再次使用BubbleSortAsc:
result=names[i].compareToIgnoreCase(names[i+1]);
if(result>0) //names[i] > names[i+1], so swap them.
在BubbleSortDesc中:
result=names[i].compareToIgnoreCase(names[i+1]);
if(result<0) // This was backwards. If names[i] < names[i+1], you need to swap, for descending order.
答案 1 :(得分:0)
实际上你真的很难
对于冒泡排序:
另外我猜你做得非常困难,你可以对它们进行排序并打印出来:
...
for(int i = 0; i < (names.length - 1); i++){
for(int j = i; j < (names.length - 1); j++){
if(names[j].compareToIgnoreCase(names[i]) > 0){
String aux = names[i];
names[i] = names[j];
names[j] = aux;
}
}
}
for(int i = 0; i < names.length; i++){
System.out.println(names[i]);
}
for(int i = 0; i < (names.length - 1); i++){
for(int j = i; j < (names.length - 1); j++){
if(names[j].compareToIgnoreCase(names[i]) < 0){
String aux = names[i];
names[i] = names[j];
names[j] = aux;
}
}
}
for(int i = 0; i < names.length; i++){
System.out.println(names[i]);
}
...
希望这有帮助