Convert a String to Float

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

float custom_atof(const char *str) {
    // Your logic here
    int length = 0;
    float value = 0;
    bool flag = 0;
    int dem = 0;
    while (str[length] != '\0') {
        if (str[length] == '.') flag = 1;
        if (str[length] >='0' && str[length] <='9') {
            value = value*10 + (str[length] - '0');
            if (flag == 1) dem++;
        }
        length++;
    }
    for (int i = 0; i < dem; i++) {
        value = value/10;
    }
    if (str[0] == '-') value = value*-1;

    return value;
}

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;
}