Forgetting Semicolons

When you forget a semicolon in C++, the compiler will generate an error because it can't figure out where one statement ends and the next begins. The error messages can sometimes be confusing though!

Let's look at an example:

1#include <iostream>
2using namespace std;
3
4int main() {
5  // missing semicolon!
6  cout << "First line\n"   
7  cout << "Second line\n";
8}

1error: expected ';' before 'cout'

The compiler tries to help by pointing to where it got confused, but sometimes the error appears on the line after the missing semicolon. This is because C++ doesn't know a statement is supposed to end until it hits either a semicolon or something that can't possibly be part of the current statement.

To make your code easier to debug:

• Add semicolons as you write each line, don't wait until the end
• When you get errors, always check the line before the error for a missing semicolon
• Use proper indentation to make statement boundaries clearer
• Most modern IDEs will highlight missing semicolons as you type

Remember: In C++, semicolons are statement terminators, not line terminators. This means you can actually write multiple statements on one line (though it's not recommended for readability):

1#include <iostream>
2using namespace std;
3
4int main() {
5  cout << "One"; cout << "Two"; cout << "Three";  
6}

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