/*  howpow2.cpp  by K.Tsuru  */ 
// function ID = 002
/*****************************************
SNumber sub-function
Return a value n which satisfies a condition  p<= 2^n.
e.g.   p = 5 --> n = 3
*****************************************/
#ifndef TYPEDEF_H
#include "typedef.h"
#endif

uint howpow2(uint p){
    if(p < 2) return 0;
    uint j = 0, k = 1;
    while(k < p){   k *= 2;     j++;    }
    return j;
}