Convert a String to Float

Code

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

float custom_atof(const char *str) {
    // Your logic here
    int sign = 1;
    int i = 0, res = 0;
    int len = 0, index;
    float reg;
    if(str[i] == '+'){
        i++;
    }
    else if (str[i] == '-'){
        sign = -1;
        i++;
    }
    while(str[i]){
        if(str[i] == '.'){
            index = i;
            i++;
        }
        res = res * 10 + (str[i] - '0');
        len = i;
        i++;
    }
    reg = res * 1.0;
    if( index != 0){
        for(int j = 0; j < len - index; j++){
            reg /= 10;
        }
    }
    return reg * 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++;
    }

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

Solving Approach