Java/reverseString at master · sunny2121/Java · GitHub

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/*
Reverse String

Write a method that reverses a string.
For example, 'java interview' becomes 'weivretni avaj'.

*/


public String reverse(String s) {

	String rv = "";

	for (int i=0; i<s.length(); i++) {
		rv += s.charAt(s.length()-1-i);
	}
	return rv;
}


// Reverse an integer number

public int reverse(int n) {

	String s = String.valueOf(n);	// int -> String
	String rv = "";

	for (int i=0; i<s.length(); i++) {
		rv += s.charAt(s.length()-1-i);
	}
	return Integer.parseInt(rv);	// String -> int
}


//more complicated way
public String reverse(String s) {

	char[] c = s.toCharArray();

	for (int i=0; i<c.length/2; i++) {
		char tmp = c[i];
		c[i] = c[s.length()-1-i];
		c[s.length()-1-i] = tmp;
	}
	return String.valueOf(c);	// char array -> String
}