function twos_comp = twos_complement_of_binary(bin)
c=0;
temp=bin;
twos_comp=0;
while(temp>0 && rem(temp,10)==0)
twos_comp=twos_comp*10 + rem(temp,10);
temp=fix(temp/10);
c=c+1;
end
if(temp>0)
twos_comp=twos_comp*10 + rem(temp,10);
temp=fix(temp/10);
c=c+1;
end
while(temp>0)
if(rem(temp,10)==1)
twos_comp=twos_comp*10 + 0;
else
twos_comp=twos_comp*10 + 1;
end
temp=fix(temp/10);
c=c+1;
end
temp=twos_comp;
twos_comp=0;
while(c>0)
twos_comp=twos_comp*10 + rem(temp,10);
temp=fix(temp/10);
c=c-1;
end
end