Convert a String to Float

Code

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

float custom_atof(const char *str) {
    // Your logic here
    float num = 0;
    float is_decimal = 0;
    int8_t offset = -'0';
    char sign = str[0];

    if(sign == '+' || sign == '-'){
        str++;
    }

    while(*str != '\0'){
        if(*str == '.'){
            is_decimal = 0.1;
        }
        else if(!is_decimal){
            num = num * 10.0 + (float)(*str +  offset);
        }
        else{
            num = num + (float)(*str + offset) * is_decimal;
            is_decimal *= 0.1;
        }

        str++;
    }

    if(sign == '-'){
        num *= -1;
    }

    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;
}

Solving Approach