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