在主线程中的异常main java.lang.arrayIndexoutofboundsexception 1

Question

好吧，我必须做一个Java程序，确定如果给定的数字是capicua（131,12121,13431）从最后到最初的数字相同的数字。但它给了我错误，在第23行（while（i> = 0）.....）问题是我怎样才能将数组调用到whileh中。请帮助我真的很伤心：c。下面是代码：

public class Capi { 
    /** 
    * 
    **/ 
    public static int num(int a) { // counting digits from the number 
    int n = 0; 
    while(a>=10) { a = a/10; 
      n = n+1; 
      } 
    return n; 
    } 
    public static boolean det(int a, int n) { 
    int z = a; 
    double y =0; 
    n = n-1; 
    int i = 0; 
    int x[] = new int[n]; 
    for(i=0; i<x.length; i++) { // saving the digits into x[i] 
     x[i] = a%10; 
     a = a/10; 
     } 
    while(i>=0) { y = x[i]*Math.pow(10,n-1); // calling the digits x[i],x[i-1] untill it gets 0 
     i = i - 1; 
     n = n -1; 
      } 
    double num1= y + a*Math.pow(10,n); 
    if(num1 == z) { return true; } 
    else { return false; } 
    } 
} 

Answer 1

我觉得这个问题是我的值设置为x.length，尝试while(i>=0)之前。因此，在运行循环之前，我已添加i--。

看看下面是否有窍门。

public class Capi { 

public static int num(int a) { // counting digits from the number 
    int n = 0; 
    while(a>=10) { 
     a = a/10; 
     n = n+1; 
    } 
    return n; 
} 

public static boolean det(int a, int n) { 
    int z = a; 
    double y = 0; 
    n = n-1; 
    int i = 0; 
    int x[] = new int[n]; 

    for(i=0; i<x.length; i++) { // saving the digits into x[i] 
     x[i] = a%10; 
     a = a/10; 
    } 

    //i is now set to x.length, thus decrement it as index runs from 0 to x.length-1 
    i=i-1; 

    while(i>=0) { 
     y = x[i]*Math.pow(10,n-1); // calling the digits x[i],x[i-1] untill it gets 0 
     i = i - 1; 
     n = n -1; 
    } 

    double num1= y + a*Math.pow(10,n); 
    if(num1 == z) { 
     return true; 
    } 
    else { 
     return false; 
    } 
} 

}