char buf[1200000]; int y[100000]; int main() { char*r=buf,*w=buf; read(0,buf,sizeof buf); int c; int n=0; while(c=*r++-48,c>=0)n=n*10+c; int s=0; for(int i=0;i=0)v=v*10+c; s+=y[i]=f?-v:v; } int n1=n-1; for(int i=0;i