function [num_unconnect,cnstrt1,cnstrt2,cnstrt3,cnstrt4]=connect_check(a,b,c)
num_unconnect=zeros(4,1);
cnstrt1 = -1-a(:)-b(:)-c(:);
cnstrt2 = -(-1+a(:)+b(:)-c(:));
cnstrt3 = -(1-a(:)+b(:)-c(:));
cnstrt4 = -(1+a(:)-b(:)-c(:));
num_unconnect(1)=sum(cnstrt1>0);
num_unconnect(2)=sum(cnstrt2>0);
num_unconnect(3)=sum(cnstrt3>0);
num_unconnect(4)=sum(cnstrt4>0);
end