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Snippet

Structs vs Classes: What's the Difference?

In C++, structs and classes are nearly identical - both can have member functions, access specifiers, and constructors. The key difference is their default access level: structs default to public, classes default to private. Structs are traditionally used for simple data containers (POD - Plain Old Data), while classes are used when you need encapsulation and data hiding. For modern C++, the choice is mostly stylistic.

snippet.cpp
cpp
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#include <iostream>
 
struct PointStruct {
int x;
int y;
void print() {
std::cout << "Struct: (" << x << ", " << y << ")" << std::endl;
}
};
 
class PointClass {
public:
int x;
int y;
void print() {
std::cout << "Class: (" << x << ", " << y << ")" << std::endl;
}
};
 
int main() {
PointStruct s1 = {10, 20};
s1.print();
PointClass c1;
c1.x = 30;
c1.y = 40;
c1.print();
PointStruct s2;
s2.x = 50;
s2.y = 60;
s2.print();
return 0;
}
Breakdown
1
struct PointStruct {
Struct definition - members default to public access
2
int x; int y;
Public member variables by default in structs
3
PointStruct s1 = {10, 20};
Aggregate initialization allowed with structs
4
class PointClass {
Class definition - members default to private access
5
public:
Explicit access specifier needed to make members accessible
6
c1.x = 30;
Accessing public members of a class object