104 lines
1.9 KiB
Go
Executable File
104 lines
1.9 KiB
Go
Executable File
// CookieJar - A contestant's algorithm toolbox
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// Copyright (c) 2013 Peter Szilagyi. All rights reserved.
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//
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// CookieJar is dual licensed: use of this source code is governed by a BSD
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// license that can be found in the LICENSE file. Alternatively, the CookieJar
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// toolbox may be used in accordance with the terms and conditions contained
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// in a signed written agreement between you and the author(s).
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// Package mathext contains extensions to the base Go math package.
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package mathext
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import "math/big"
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const (
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maxInt = int(^uint(0) >> 1)
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minInt = int(-maxInt - 1)
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)
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// AbsInt returns the absolute value of the x integer.
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//
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// Special cases are:
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// AbsInt(minInt) results in a panic (not representable)
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func AbsInt(x int) int {
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if x >= 0 {
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return x
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}
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if x == minInt {
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panic("absolute overflows int")
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}
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return -x
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}
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// MaxInt returns the larger of x or y integers.
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func MaxInt(x, y int) int {
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if x > y {
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return x
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}
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return y
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}
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// MaxBigInt returns the larger of x or y big integers.
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func MaxBigInt(x, y *big.Int) *big.Int {
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if x.Cmp(y) > 0 {
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return x
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}
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return y
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}
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// MaxBigRat returns the larger of x or y big rationals.
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func MaxBigRat(x, y *big.Rat) *big.Rat {
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if x.Cmp(y) > 0 {
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return x
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}
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return y
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}
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// MinInt returns the smaller of x or y integers.
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func MinInt(x, y int) int {
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if x < y {
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return x
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}
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return y
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}
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// MinBigInt returns the smaller of x or y big integers.
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func MinBigInt(x, y *big.Int) *big.Int {
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if x.Cmp(y) < 0 {
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return x
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}
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return y
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}
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// MinBigRat returns the smaller of x or y big rationals.
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func MinBigRat(x, y *big.Rat) *big.Rat {
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if x.Cmp(y) < 0 {
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return x
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}
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return y
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}
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// SignInt returns the sign of the x integer.
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func SignInt(x int) int {
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switch {
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case x > 0:
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return 1
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case x == 0:
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return 0
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default:
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return -1
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}
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}
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// SignFloat64 returns the sign of the x floating point number.
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func SignFloat64(x int) int {
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switch {
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case x > 0:
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return 1
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case x == 0:
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return 0
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default:
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return -1
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}
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}
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