#include <stdio.h>
#include <stdint.h>
int custom_atoi(const char *str) {
// Your logic here
int x = 0, sgn = 1;
switch(*str){
case('-'):
sgn = -1;
case('+'):
str++;
}
for(;*str != '\0';str++){
if(*str < '0' || *str > '9')
break;
x = x * 10 + (int)(*str - '0');
}
x *= sgn;
return x;
}
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;
}