Additive Operators: + and 
expression + expression expression – expression
The additive operators are:

Addition (+)

Subtraction (–)
These binary operators have lefttoright associativity.
The additive operators take operands of arithmetic or pointer types. The result of the addition (+) operator is the sum of the operands. The result of the subtraction (–) operator is the difference between the operands. If one or both of the operands are pointers, they must be pointers to objects, not to functions. If both operands are pointers, the results are not meaningful unless both are pointers to objects in the same array.
Additive operators take operands of arithmetic, integral, and scalar types. These are defined in the following table.
Type  Meaning 

arithmetic  Integral and floating types are collectively called "arithmetic" types. 
integral  Types char and int of all sizes (long, short) and enumerations are "integral" types. 
scalar  Scalar operands are operands of either arithmetic or pointer type. 
The legal combinations for these operators are:
arithmetic + arithmetic
scalar + integral
integral + scalar
arithmetic – arithmetic
scalar – scalar
Note that addition and subtraction are not equivalent operations.
If both operands are of arithmetic type, the conversions covered in Arithmetic Conversions are applied to the operands, and the result is of the converted type.
// expre_Additive_Operators.cpp // compile with: /EHsc #include <iostream> #define SIZE 5 using namespace std; int main() { int i = 5, j = 10; int n[SIZE] = { 0, 1, 2, 3, 4 }; cout << "5 + 10 = " << i + j << endl << "5  10 = " << i  j << endl; // use pointer arithmetic on array cout << "n[3] = " << *( n + 3 ) << endl; }