#include <stdio.h>
int main()
{
register char c = 0, s = 0;
int n;
n=0;
while(c<33) c=getc_unlocked(stdin);
if(c==45) {s=1; c=getc_unlocked(stdin);}
while(c>32) {n=(n<<3)+(n<<1)+(c-48); c=getc_unlocked(stdin);}
if(s==1) n=-n;
return(0);
}
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