#include <stdio.h>
#include <stdint.h>
int custom_atoi(const char *str) {
// Your logic here
bool neg = false;
int start = 0;
if(str[0] == '-')
neg = true;
if(str[0] == '-' || str[0] == '+')
start = 1;
int result = 0;
for (int i = start; str[i] >= '0' && str[i] <= '9'; i++)
{
result = result*10 + (str[i] - '0');
}
return neg ? 0-result : result;
}
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;
}