how do loops work in c++ code example

Example 1: c++ for loop

//'i' can be any number
//Can be any comparison operater 
//can be any number compared
//can be any mathmatic operater

for (int i = 0; i<100; i++){
//Do thing
}

//more info on operaters
//https://www.w3schools.com/cpp/cpp_operators.asp

Example 2: how to make a Loop in c++

for (int i; i < 10; i++)
{
  cout << i << "\n";
}