reverse string with recursion
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class Main {
public static void main(String[] args) {
System.out.println(recStringRev("hello",0));
}
public static String recStringRev(String s, int a) {
if(a >= s.length()){
return "";
}
char ch = s.charAt(a);
String rev = recStringRev(s,a+1);
return rev + ch;
// reverse loop
// we can use a stack to reverse
// here we will try recursion
}
// Public method
public static int reverse(int n) {
return reverseHelper(n, 0);
}
// Recursive helper function
private static int reverseHelper(int n, int rev) {
// Base case
if (n == 0) return rev;
int last = n % 10; // get last digit
rev = rev * 10 + last; // append to reversed number
return reverseHelper(n / 10, rev); // recursive call
}
}
Java
INFO