Given a string str, the task is to print the first and the last character of the string. Examples:
Input: str = “GeeksForGeeks” Output: First: G Last: s Explanation: The first character of the given string is ‘G’ and the last character of given string is ‘s’. Input: str = “Java” Output: First: J Last: a Explanation: The first character of given string is ‘J’ and the last character of given string is ‘a’.
Method 1: Using String.charAt() method
- The idea is to use charAt() method of String class to find the first and last character in a string.
- The charAt() method accepts a parameter as an index of the character to be returned.
- The first character in a string is present at index zero and the last character in a string is present at index length of string-1.
- Now, print the first and last characters of the string.
Below is the implementation of the above approach:
Java
// Java program to find first// and last character of a stringclass GFG { // Function to print first and last // character of a string public static void firstAndLastCharacter(String str) { // Finding string length int n = str.length(); // First character of a string char first = str.charAt(0); // Last character of a string char last = str.charAt(n - 1); // Printing first and last // character of a string System.out.println("First: " + first); System.out.println("Last: " + last); } // Driver Code public static void main(String args[]) { // Given string str String str = "GeeksForGeeks"; // Function Call firstAndLastCharacter(str); }} |
Output
First: G Last: s
Method 2: Using String.toCharArray() method
- The idea is to first convert the given string into a character array using toCharArray() method of String class, then find the first and last character of a string and print it.
Below is the implementation of the above approach:
Java
// Java program to find first// and last character of a stringclass GFG { // Function to print first and last // character of a string public static void firstAndLastCharacter(String str) { // Converting a string into // a character array char[] charArray = str.toCharArray(); // Finding the length of // character array int n = charArray.length; // First character of a string char first = charArray[0]; // Last character of a string char last = charArray[n - 1]; // Printing first and last // character of a string System.out.println("First: " + first); System.out.println("Last: " + last); } // Driver Code public static void main(String args[]) { // Given string str String str = "GeeksForGeeks"; // Function Call firstAndLastCharacter(str); }} |
Output
First: G Last: s
Time complexity: O(1)
Auxiliary space: O(n) because it is using extra space for charArray
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