write a program to find first non repeat character in a string?

Here we pass the string in a for loop and through charAt method we converted in character.
from indexOf() method returns the position of the first occurrence of a given character in a string whereas method lastIndexOf() method returns the position of the last occurrence of a given character in a string.
if the indexOf() and lastIndexOf() methods return the same position of given character are the same, then that character is the first non repeat character in a string.

				
					public class FirstNonRepeatChar {
	public static String repeat(String str) {
		for (int i = 0; i < str.length(); i++) {
			char c = str.charAt(i);
			if (str.indexOf(c) == i && str.indexOf(c, i + 1) == -1) {
				return String.valueOf(c);
			}
		}
		return "non repeat";
	}

	public static void main(String[] args) {
		String str = "wwellcomewe";
		System.out.println(FirstNonRepeatChar.repeat(str));
	}
}

Output:- c

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