#include <stdio.h>


long long scanNum(void){

int i,  chk;

long long result;

char inp[20];

do{

chk = result= 0;

scanf("%s", inp);

for(i=0;inp[i];i++){

if(inp[i]<'0' || '9'<inp[i]){

//!('0' <= inp[i] && inp[i] <= '9')

chk=1;

break;

}

result *= 10;

result += (inp[i]-'0');

}

}while(chk);

return result;

}


int main(void){

printf("%lld\n", scanNum());

return 0;

}



음..