C++ - decrement operator
The decrement (--) is an unary operator in C++ and hence acts upon a single operand to produce a new value. It has two variant:
- Pre-decrement: Decreases the value of the operand by 1, then returns the operand.
- Post-decrement: Returns the operand, then decreases the value of the operand by 1.
Example: Pre-decrement operator
The example below describes the usage of pre-decrement operator.
#include <iostream> using namespace std; int main (){ int x = 10; int y = 20; int z; //below expression is equivalent to //x = x - 1; z = x + y; z = --x + y; //Displaying the result cout<<"x = "<<x<<"\n"; cout<<"y = "<<y<<"\n"; cout<<"z = "<<z<<"\n"; return 0; }
The output of the above code will be:
x = 9 y = 20 z = 29
Example: Post-decrement operator
The example below describes the usage of post-decrement operator.
#include <iostream> using namespace std; int main (){ int x = 10; int y = 20; int z; //below expression is equivalent to //z = x + y; x = x - 1; z = x-- + y; //Displaying the result cout<<"x = "<<x<<"\n"; cout<<"y = "<<y<<"\n"; cout<<"z = "<<z<<"\n"; return 0; }
The output of the above code will be:
x = 9 y = 20 z = 30
❮ C++ - Operators