#include <stdio.h>
#include <stdint.h>
#include <math.h>
float custom_atof(const char *str) {
float val = 0;
int i = 1;
const char *ptr = str;
if (*ptr == '-' || *ptr == '+')
ptr++;
// Parse integer part
while (*ptr && *ptr != '.') {
val = val * 10 + (*ptr - '0');
ptr++;
}
// Parse fractional part only if '.' exists
if (*ptr == '.') {
ptr++;
while (*ptr) {
val += (*ptr - '0') / pow(10, i);
ptr++;
i++;
}
}
if (*str == '-')
val = -val;
return val;
}
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;
}
Input
123.45
Expected Output
123.45