Convert String to Integer

Code

#include <stdio.h>
#include <stdint.h>

int custom_atoi(const char *str)
 {
  int i=0,digit=0,sign=1,num=0;
  if(str[i]=='-')
  {
    sign = -1;
    i++;
  }
  if(str[i]=='+')
  {
    sign = 1;
    i++;
  }
  for(i;str[i] >='0' && str[i]<='9' && str[i]!='\0';i++)
  {
    digit=str[i] - '0';
    num=num*10 +digit;
  }
    return num *sign;
}

int main() {
    char str[101];
    fgets(str, sizeof(str), stdin);

    // Remove newline
    uint8_t i = 0;
    while (str[i]) {
        if (str[i] == '\n') {
            str[i] = '\0';
            break;
        }
        i++;
    }

    printf("%d", custom_atoi(str));
    return 0;
}

Solving Approach