Lab 1

Learn how to use GIT

Learn simple command:

Each student will create his/hers private GITHUB repository where his/her teaching assistant will be set as a collaborator for that repo. All of the operations from now on (lab exams, lab homework will be done via that repo (or multiple repos) ).

1. Recap simple C library functions

Write a program in C-Language that open the file "in.txt", and prints the sum of the numbers that are found on each line of the file "in.txt". To open the file use fopen API. Write your own function that converts a string to a number (similar cu atoi API). To print something to the screen, use the printf API.

Example: let's consider the following "ini.txt" file:

The program will print to the screen 1187109.

2. Recap scanf/printf

Read a sentence from the input using scanf API. Then sort split it into words and write to the screen (using the printf API) the words sorted (from the longest one to the shortest one).If two words have the same length - they will be sorted out alphabetically. We consider that each word is separated from another one using space (one or multiple).

Example: let's consider the following sentence: `"I went to the library yesterday"``. The program will print the following to the screen:

yesterday
library
went
the
to
I

3. Some C and C++ problem

Lets consider the following code:

#include <iostream>
using namespace std;

bool isPrime(int n)
{
    for (int tr = 2; tr < n / ......; tr++)
        if ((n % ...... ) == 0)
            return ......;
    return true;
}
int main()
{
    int n;
    std::cout << "Enter a number:";
    std::cin >> ......;
    if (isPrime(n))
        std::cout << n << " is prime !";
    else 
        std::cout << n << " is NOT prime !";
    return 0;
}

Fill in the missing code (dots: ...... ) to make this program work as expected.