var ipA=new byte[]{91,201,64,0};
var ipB=new byte[]{91,201,67,255};

var nipA = (ipA[0]<<24)+(ipA[1]<<16)+(ipA[2]<<8)+ipA[3];
var nipB = (ipB[0]<<24)+(ipB[1]<<16)+(ipB[2]<<8)+ipB[3];

var...