/*****************************************************
File name atof Author crowbar erey_Jobs Version:0.1 Date:
*****************************************************/
#include <stdio.h>
double atofmy(const char *str)
{
double s = 0.0;
double d = 10.0;
int jishu = 0 ;
double flag=1.0;
while((*str >=‘a’&&*str<=‘z’)|| (*str>=‘A’&&*str<=‘Z’))
{
str ++;
}
if(*str ==’-’)
{
flag = -1.0 ;
str ++;
}
while(*str >= ‘0’ && *str<= ‘9’ && str != ‘.’ )
{
s = s10.0 +*str -‘0’;
str ++;
}
if(*str ==’.’)
str ++;
while (*str >=‘0’ && *str <=‘9’)
{
s=s+(str - ‘0’)/d;
d=10.0;
str++;
}
if(*str == ‘e’ ||*str ==‘E’)
{
str++;
if(*str == ‘+’)
{
str++;
while(*str >= ‘0’ && str <=‘9’)
{
jishu=jishu10 +str -‘0’;
str++;
}
while (jishu>0)
{
s=10;
jishu --;
}
}
if(*str == ‘-’)
{
str++;
while(*str >= ‘0’ && str <=‘9’)
{
jishu =jishu10 + str - ‘0’;
str ++;
}
while(jishu >0)
{
s/=10;
jishu --;
}
}
}
return sflag;
}
int main()
{
char *str;
double num ;
gets(str);
num = atofmy(str);
printf("%lf" , num);
return 0;
}