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