Re: (part 5) Han from China answers your C questions

Borked Pseudo Mailed <nobody@xxxxxxxxxxxxxxxxx> writes:

a question abou "atoi"
66650...@xxxxxx said:
First,thanks for all who have answered my last question.

if char string[20]="12345";

how could I convert the string[2](that is "3") to an int by using
atoi? I only want to convert string[2],not other string[i].

int a;
char string[20]="12345";

atoi((a=string[2]-'0',"X"));

The consensus is that this exhibits undefined behaviour (quite apart
from being silly). If the OP really needs to use atoi to do this
simple conversion, the easiest way would probably be:

a = atoi((char []){string[2], 0});

--
Ben.
.

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