如何使用遞歸在單個變量中反轉java中的數字？

Question

//Is there any simple idea other than it? 
static int rev(int n){ 
    if (n==0)return 0; 
    else return n%10^10+rev(n/10) 
} 

我想用單變量和遞歸來反轉數字。

Answer 1

//Here i got the idea. 
public static void main(String[] args) { 
    // Let the number be 139. 
    int n=139; 
    System.out.println("reverse is "+rev(n)); 
} 
static int rev(int n){ 
    if (n<10)return n; 
    else return n%10*(int) Math.pow(10,(int)Math.log10(n))+rev(n/10); 
     //Math class is used to return the number of digits and power. 
} 

這給::反向是931