How to cleared constant in C++ programming
Keyword Constant in C++
When we declared some constant in C++ then we cannot Change its value and it is called constant. write the keyword const before declaring canstant.
Syntax
const int a=20;
const float pi=3.14;
Note: A constant must be initialize to some value other wise you will get error in C++.
Example 1
#include<iostream.h>
int main()
{
const int a=5;
cout<<a;
system("pause");
return 0;
};
output: 5
Example 2
int main()
{
const int a;
a=5;
cout<<a;
system("pause");
return 0;
};
Output: error you are not initialize your constant
Example 3
int main()
{
const int a=5;
a=9;
system("pause");
return 0;
};
Output:
error you cannot change the value of a because it is constant.
