Disclosure: I work on GTU Hero, a site for GTU (Gujarat Technological University) exam prep. This is aimed at first-year engineering students taking Programming for Problem Solving.

If you are new to C, these eight programs cover most of the basics you will be tested on: conditions, loops, integer arithmetic and recursion.

Program Concept it tests
Even or odd if-else, %
Factorial loops, recursion
Prime check loops, flags, edge cases (1 is not prime)
Fibonacci updating two variables
Sum of digits % 10 and / 10
Reverse and palindrome temp variables
Largest of three comparisons, equal inputs
Armstrong number digit extraction, powers

Here is the simplest one, to show the style GTU expects (write the algorithm too):

#include <stdio.h> int main(void) { int n; printf("Enter a number: "); scanf("%d", &n); if (n % 2 == 0) printf("Even number"); else printf("Odd number"); return 0; } 

Edge cases are where marks go. Test prime check with 1 and 2, test largest-of-three with equal values, and test palindrome with a single digit.

For GTU specifically, PPS appears under codes like 3110003 and BE01000121, so match your code before using old papers. The full list with past paper links is here: GTU Hero PPS guide.