How does switch statement compares values? [duplicate]

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• Does case-switch work like this? 5 answers

Given the following sequence

switch(1) {
    case 1:
        cout << "first \n";
    case 2:
        cout << "second \n";
    default:
        cout << "Not first nor the second";
}

the output is

first 
second 
Not first nor the second

I'm expecting the output to be

first

so, how do values are compared? I know I didn't use the break statement, but isn't that just to save cpu time? How come the second case executes since there are two different integer values? What am I missing?

I'm using gcc 4.9.2 with -std=c++11 flag.