/*  mathtp.h  by K.Tsuru  */
/********************************
Mathematical template functions
include non ANSI functions.
*********************************/
#ifndef MATH_TEMPLATE_H
#define MATH_TEMPLATE_H
#include <iostream>     // added since ver 2.21
#include <algorithm>    // for min() and max() since ver 2.19
using namespace std;    // ver. 2.19

/**************************************************
It returns 10^n by long, defined in "ipow10.cpp"
If n < 0, it returns 0.
It does not check that 10^n < LONG_MAX.
***************************************************/
long ipow10(int n);

/**************************************************
10^n double version defined in "dpow10.cpp"
'n' can be negative.
[notice] "pow(10.0, 2)" returns 99.999999.... , then
int k = pow(10.0,2); you get k=99.
***************************************************/
double dpow10(const int n);

// difference |a-b|
template <class Type> inline Type diff(Type a, Type b){
   return  (a > b) ? (a - b) : (b - a);
}
// sign of a, when a == 0 return zero.
template <class Type> inline int Sgn(Type a){
    if(a != 0) return ( a > 0 ) ? 1 : -1;
    return 0;
}

// It returns "true" if x and y have same sign.
template <class Type> inline bool sameSign(Type x, Type y){ // ver 2.17
    return (x > 0) == (y > 0);
}

// return the figures of n. n must have integer type.
template <class Type> int iFigures(Type n){
    int f = 0;
    while(n){
        n /= (Type)10;
        f++;
    }
    return f;
}
// "n" is 2^n ? since ver.2.18
template <class Type> inline  bool isPow2(Type n){
    return (n > 0) && ( (n & (n - 1)) == 0 );
}

// return ceil(u/v)
template <class Type> inline Type ceil(Type u, Type v){
    Type n = u/v;
    if(u % v) n++;
    return n;
}
/*******************
 usable for SLong, SDouble class
 usage : cin >> a; ( s = cin )
********************/
template <class Type> inline istream& operator>>(istream& s, Type& a) // added since version 2.21
{
    string buf;
    std::getline(s, buf);
    a = buf.data();
    return s;
}
#endif  // MATH_TEMPLATE_H