Why is it that an int in C++ that isnt initialized (then used) doesn't return an error?
- by omizzle
I am new to C++ (just starting). I come from a Java background and I was trying out the following piece of code that would sum the numbers between 1 and 10 (inclusive) and then print out the sum:
/*
* File: main.cpp
* Author: omarestrella
*
* Created on June 7, 2010, 8:02 PM
*/
#include <cstdlib>
#include <iostream>
using namespace std;
int main() {
int sum;
for(int x = 1; x <= 10; x++) {
sum += x;
}
cout << "The sum is: " << sum << endl;
return 0;
}
When I ran it it kept printing 32822 for the sum. I knew the answer was supposed to be 55 and realized that its print the max value for a short (32767) plus 55. Changing
int sum;
to
int sum = 0;
would work (as it should, since the variable needs to be initialized!). Why does this behavior happen, though? Why doesnt the compiler warn you about something like this? I know Java screams at you when something isnt initialized.
Thank you.
