Convert a String to Float

Code

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

float custom_atof(const char *str) {
    // Your logic here
    float num = 0;
    char sign;
    int flg = 0;
    float frac =0;
    
    while(*str !='\0') {
        if(*str == '+' || *str == '-') {
            sign = *str;
            str++;
            continue;
        } 

        if((*str >= '0' && *str <= '9')&& (flg == 0)) {
            num = num * 10 + (*str - '0');
        } 
        else if(flg == 1) {
            frac = frac * 10 + (*str - '0');
        } 
        else {
            flg = 1;
        }
        str++;
    }
    if(frac == 1) {
        frac = frac * 0.001;
    } 
    else {
        frac = frac * 0.01;
    }
    num = num + frac;
    if(sign == '-') {
        num = 0 - num;
    }
    return num;
}

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++;
    }

    float value = custom_atof(str);
    printf("%.2f", value);
    return 0;
}