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