Convert a String to Float

Code

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

float custom_atof(const char *str) {
    // Your logic here
    float res = 0.0f;
    float divisor = 1.0f;
    int after_dot = 0;
    int i = 0;
    int sign = 1;

    if (str[i] == '-') {
        sign = -1;
        i++;
    }
    else if (str[i] == '+') {
        i++;
    }
    for(; str[i] != '\0'; i++){
        if(str[i] >= '0' && str[i] <= '9'){
            if(!after_dot){
                res = res * 10 + (str[i] - '0');
            }
            else{
                divisor *= 10;
                res = res + (str[i] - '0') /divisor;
            }
        }
        else if(str[i] == '.'){
            after_dot = 1;
        }
        else{
            break;
        }
    }
    return sign * res;
}

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;
}

Solving Approach