Apparently you have been taught on a different level of programming than this. The questions are quite basic if you ever worked with Linux or UNIX. Perhaps check job requirements next time. 1) cat concatenates the content of the second file to the content of the first and outputs it (to the screen unless redirected ) open file one until EOF // end of file c = getc file1 copies the content of the second file to the content of the first and outputs it the console print c close file 1 same for file 2 Question 2 The answer given previously would work but is perhaps tricky Simpler (but more time-consuming) would be go through the string from the first character to the last // this needs a for-loop check if the current character appears in the rest of the string // another for loop from the current + 1 position of the string to the end if that is the case BINGO! otheriwise go ahead

1. Loop through all the characters for the string char array. 2. If you are doing this in Java, use indexOf and lastIndexOf methods. 3. If indexOf and lastIndexOf are same then you have found your first unique char. for(char character : input.toCharArray()) { if(input.indexOf(character) == input.lastIndexOf(character)) { print character; return; } }

import java.util.*; public class HelloWorld{ public static void main(String []args){ System.out.println(unique("assaiieerrfufuqppp")); } public static char unique(String str) { Map freq = new LinkedHashMap(); for(int i=0; i