c - Data types storage -

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• how c handle integer literals leading zeros, , atoi? 7 answers

the following code prints 255, if assigned 0255 x, in second line, code prints 173!

is there explanation this?

void main() {     unsigned long x = 255;     /* unsigned long x = 0255;*/     unsigned char *ptr = &x;     printf("%u",*ptr);     getch(); } 

when number has '0' in front of other digits, it's treated octal number. , 255 in octal 173 in decimal.