When we initialize a value by putting '0' before a number, the number is treated as octal. For instance '10' is read as 10 but '010' is read as 8. Octal numbers are the numbers with base 8 and octal literals are used to represent the octal integer values
Example
Input : 0101
Output : 65
Input : 01010
Output : 520
Examples of Octal Literals
Example 1
// C Program to illustrate octal literals in C
#include <stdio.h>
int main()
{
// initializing an integer with an octal literal i.e.
// starts with zero
int x = 0101;
printf("x = %d", x);
return 0;
}
Output
x = 65
Example 2
// C Program to illustrate the octal literals
int main()
{
int x = 020; // int with 20 octal value
printf("x = %d", x);
return 0;
}
Output
x = 16
Example 3
As the octal number system only have 8 digits, we cannot use 8 and 9 numbers as a digit in octal literal.
// C Program to illustrate the octal literals
#include <stdio.h>
int main()
{
int x = 080;
printf("x = %d", x);
return 0;
}
Output
Compiler Error : 8 is not a valid digit in octal number.