Can anyone help me with my problem?

Problem : I have 4 text files named datatypes, delimiters, operators and variables, having respective data. I have another file which acts as input to this program. The problem is that I have to check each lexeme of the input file and compare it with the content of each file listed before. Whenever the match is found, it should display appropriate result on the console of Turbo C and should reflect the same result in a text file.

Kind of difficult for us to give you any advice without knowing the contents of the files. Post a few lines from each file so that we can see what you are talking about.