Convert a String to Float

Code

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

float custom_atof(const char *str) {
    
    float number = 0;

    char buffer[256];

    uint8_t buffer_index=0;

    memset(buffer,'\0',sizeof(buffer));

    for(int i=0; str[i]!='\0'; i++)
    {
        if(isdigit(str[i]) || str[i]=='.' ||  str[i]=='-' ||  str[i]=='+')
        {
            buffer[buffer_index] = str[i];
            buffer_index++;
        }
    }

    buffer[buffer_index] = '\0';
    
    sscanf(buffer,"%f",&number);

    return number;
}

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