I am trying to do a project in C which needs following input method from a text file:

Without using file operations inside a C program how we can write a program as reading the data from the standard input, and use the operating systems (example: linux) redirection ability to have the program read the data from a text file and use those data for calculation .

Please help to write the code to read the data from a text file. But not using the file operation. Sample of the input file is as follows:

START PointS P1 0.89 P4 P1 0.91 P2 P1 0.93 P3 P2 0.87 P3 P2 0.88 P3 P3 0.97 P4 P3 0.94 P4 P4 0.95 P5 P5 0.96 P6 END PointE