#include <stdio.h>
#include <stdint.h>
int custom_atoi(const char *str)
{
int sign = 1;
int i = 0;
int result = 0;
if(str[i] == '-')
{
sign = -1;
i++;
}
else if(str[i] == '+')
{
i++;
}
while(str[i] >= '0' && str[i] <= '9')
{
result = result*10 + (str[i]-'0');
i++;
}
return sign * result;
}
int main()
{
char str[101];
fgets(str,sizeof(str),stdin);
uint8_t i = 0;
while(str[i])
{
if(str[i]=='\n')
{
str[i]='\0';
break;
}
i++;
}
printf("%d",custom_atoi(str));
return 0;
}