Self-writing atoi----strings into shaping

Strings are converted into various cases of shaping:

       char *str1 = "12345";      //normal
< /span>char *str2 = "+12345";    //positive
char *STR3 = " -12345";      //negative
char *STR4 = "  12345";    //preceded by a number of spaces
char *STR5 = "1 2 3 4 5"; There are spaces between  //numbers
char *STR6 = "0x12345";    //hex
char *str7 = "012345";    //Eight binary
char *str8 = "abc123";    //with other characters

Char *str2 = "+12345"; Positive
Char *STR3 = "12345"; Negative
Char *STR4 = "12345"; There are a number of spaces in front
Char *STR5 = "1 2 3 4 5"; There are spaces between numbers
Char *STR6 = "0x12345"; Hexadecimal
Char *STR7 = "012345"; Octal

Char *str8 = "abc123"; with other characters

The code is as follows:

#include <stdio.h>int my_atoi (const char *str) {int result = 0;        Store the converted value int sign = 1;     Sign bit int weight = 10;       Weights (decimal, octal, hex) while (*str! = ') ') {if (*str = = ' + ')//indicates positive number {sign = 1;str++;       Will ' + ' skim}if (*str = = '-')//indicate negative number {sign = -1;str++;  Will '-' skim}/*if (*str = = ' 0 ' && * (++str)! = ' x ') {weight = 8; Attention!!!!! : Cannot add str++ here, otherwise you will miss a character//str++; because after executing * (++STR)! = ' x ', STR has pointed to an incompletely determined character (although not equal to X)}if (*str = = ' 0 ' && * (++str) = = ' X '       )//Indicates is 16 binary {weight = 16;str++;  Will ' X ' skim}*/if (*str = = ' 0 ') {if (* (str + 1) = = ' x ') {weight = 16;str + 2;  Move ' 0 ' and ' x ' over}else{weight = 8;str + + 1; Will ' 0 ' skim}}if (*str >= ' 0 ' && *str <= ' 9 ') {result = result * weight + (*str-' 0 '); str++;} else{str++;//non-valid characters all flitted (+-0x x exp)}}return result * sign;     int main () {char *str1 = "12345";    Ordinary char *str2 = "+12345";    Positive char *STR3 = "12345";  Negative char *STR4 = "12345";   There are several spaces in front of char *STR5 = "1 2 3 4 5";//There is a space between the numbers char *STR6 = "0x12345"; Hex char *STR7 = "012345 "; octal char *str8 = "abc123";p rintf ("%6d\n", My_atoi (str1));p rintf ("%6d\n", My_atoi (str2));p rintf ("%6d\n", My_atoi ( STR3));p rintf ("%6d\n", My_atoi (STR4));p rintf ("%6d\n", My_atoi (STR5));p rintf ("%6d\n", My_atoi (STR6));p rintf ("%6d\n ", My_atoi (STR7));p rintf ("%6d\n ", My_atoi (STR8)); return 0;}

Self-writing atoi----strings into shaping