gecko-dev/mfbt/tests/TestBinarySearch.cpp

159 строки
5.5 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/Assertions.h"
#include "mozilla/BinarySearch.h"
#include "mozilla/Vector.h"
#include <cstdlib>
using mozilla::ArrayLength;
using mozilla::BinarySearch;
using mozilla::BinarySearchIf;
using mozilla::Vector;
#define A(a) MOZ_RELEASE_ASSERT(a)
struct Person {
int mAge;
int mId;
Person(int aAge, int aId) : mAge(aAge), mId(aId) {}
};
struct GetAge {
Vector<Person>& mV;
explicit GetAge(Vector<Person>& aV) : mV(aV) {}
int operator[](size_t index) const { return mV[index].mAge; }
};
struct RangeFinder {
const int mLower, mUpper;
RangeFinder(int lower, int upper) : mLower(lower), mUpper(upper) {}
int operator()(int val) const {
if (val >= mUpper) return -1;
if (val < mLower) return 1;
return 0;
}
};
static void TestBinarySearch() {
size_t m;
Vector<int> v1;
MOZ_RELEASE_ASSERT(v1.append(2));
MOZ_RELEASE_ASSERT(v1.append(4));
MOZ_RELEASE_ASSERT(v1.append(6));
MOZ_RELEASE_ASSERT(v1.append(8));
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 1, &m) && m == 0);
MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 2, &m) && m == 0);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 3, &m) && m == 1);
MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 4, &m) && m == 1);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 5, &m) && m == 2);
MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 6, &m) && m == 2);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 7, &m) && m == 3);
MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 8, &m) && m == 3);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 9, &m) && m == 4);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 1, &m) && m == 1);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 2, &m) && m == 1);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 3, &m) && m == 1);
MOZ_RELEASE_ASSERT(BinarySearch(v1, 1, 3, 4, &m) && m == 1);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 5, &m) && m == 2);
MOZ_RELEASE_ASSERT(BinarySearch(v1, 1, 3, 6, &m) && m == 2);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 7, &m) && m == 3);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 8, &m) && m == 3);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 9, &m) && m == 3);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, 0, 0, &m) && m == 0);
MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, 0, 9, &m) && m == 0);
Vector<int> v2;
MOZ_RELEASE_ASSERT(!BinarySearch(v2, 0, 0, 0, &m) && m == 0);
MOZ_RELEASE_ASSERT(!BinarySearch(v2, 0, 0, 9, &m) && m == 0);
Vector<Person> v3;
MOZ_RELEASE_ASSERT(v3.append(Person(2, 42)));
MOZ_RELEASE_ASSERT(v3.append(Person(4, 13)));
MOZ_RELEASE_ASSERT(v3.append(Person(6, 360)));
A(!BinarySearch(GetAge(v3), 0, v3.length(), 1, &m) && m == 0);
A(BinarySearch(GetAge(v3), 0, v3.length(), 2, &m) && m == 0);
A(!BinarySearch(GetAge(v3), 0, v3.length(), 3, &m) && m == 1);
A(BinarySearch(GetAge(v3), 0, v3.length(), 4, &m) && m == 1);
A(!BinarySearch(GetAge(v3), 0, v3.length(), 5, &m) && m == 2);
A(BinarySearch(GetAge(v3), 0, v3.length(), 6, &m) && m == 2);
A(!BinarySearch(GetAge(v3), 0, v3.length(), 7, &m) && m == 3);
}
static void TestBinarySearchIf() {
const int v1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
const size_t len = ArrayLength(v1);
size_t m;
A(BinarySearchIf(v1, 0, len, RangeFinder(2, 3), &m) && m == 2);
A(!BinarySearchIf(v1, 0, len, RangeFinder(-5, -2), &m) && m == 0);
A(BinarySearchIf(v1, 0, len, RangeFinder(3, 5), &m) && m >= 3 && m < 5);
A(!BinarySearchIf(v1, 0, len, RangeFinder(10, 12), &m) && m == 10);
}
static void TestEqualRange() {
struct CompareN {
int mVal;
explicit CompareN(int n) : mVal(n) {}
int operator()(int aVal) const { return mVal - aVal; }
};
constexpr int kMaxNumber = 100;
constexpr int kMaxRepeat = 2;
Vector<int> sortedArray;
MOZ_RELEASE_ASSERT(sortedArray.reserve(kMaxNumber * kMaxRepeat));
// Make a sorted array by appending the loop counter [0, kMaxRepeat] times
// in each iteration. The array will be something like:
// [0, 0, 1, 1, 2, 2, 8, 9, ..., kMaxNumber]
for (int i = 0; i <= kMaxNumber; ++i) {
int repeat = rand() % (kMaxRepeat + 1);
for (int j = 0; j < repeat; ++j) {
MOZ_RELEASE_ASSERT(sortedArray.emplaceBack(i));
}
}
for (int i = -1; i < kMaxNumber + 1; ++i) {
auto bounds = EqualRange(sortedArray, 0, sortedArray.length(), CompareN(i));
MOZ_RELEASE_ASSERT(bounds.first() <= sortedArray.length());
MOZ_RELEASE_ASSERT(bounds.second() <= sortedArray.length());
MOZ_RELEASE_ASSERT(bounds.first() <= bounds.second());
if (bounds.first() == 0) {
MOZ_RELEASE_ASSERT(sortedArray[0] >= i);
} else if (bounds.first() == sortedArray.length()) {
MOZ_RELEASE_ASSERT(sortedArray[sortedArray.length() - 1] < i);
} else {
MOZ_RELEASE_ASSERT(sortedArray[bounds.first() - 1] < i);
MOZ_RELEASE_ASSERT(sortedArray[bounds.first()] >= i);
}
if (bounds.second() == 0) {
MOZ_RELEASE_ASSERT(sortedArray[0] > i);
} else if (bounds.second() == sortedArray.length()) {
MOZ_RELEASE_ASSERT(sortedArray[sortedArray.length() - 1] <= i);
} else {
MOZ_RELEASE_ASSERT(sortedArray[bounds.second() - 1] <= i);
MOZ_RELEASE_ASSERT(sortedArray[bounds.second()] > i);
}
}
}
int main() {
TestBinarySearch();
TestBinarySearchIf();
TestEqualRange();
return 0;
}