Loops.md

For loop sequence

Switch-case

• It only accepts int, char, short, long types
• break is optional, but if you do not use, the next cases will also be executed
• default is optional

char operation;
std::cin >> operation;

switch (operation)
{
    case '+': std::cout << in1+in2 << std::endl; break;
    case '-': std::cout << in1-in2 << std::endl; break;
    case '*': std::cout << in1*in2 << std::endl; break;
    case '/': std::cout << in1/in2 << std::endl; break;
    default:std::cout << "not a valid operation"<< std::endl;
}

Modern For loops

in the simple form, the actual values are not affected.

int list[3] = {1, 2, 3};
for(int i : list) // here i is just a copy
{
    i=100;
}

if you want to change the list values:

int list[3] = {1, 2, 3};
for(int &i : list) // here i is the original value
{
    i=100;
}

if you do not want to change original values, but want to avoid copying:

int list[3] = {1, 2, 3};
for(const int &i : list) // here i is the original value and not changeable
{
    i=100;
}