Finish bsearch functions.

Author: cgyurgyik

STL_examples.cpp

@@ -644,19 +644,39 @@ TEST(nth_element, ExampleOne) {
 
 // Binary search operations (on sorted ranges).
 TEST(lower_bound, ExampleOne) {
-
+ const std::vector<int> data{1,2,3,4,5,6,7,8,9,9,10};
+ const auto lower = std::lower_bound(data.cbegin(), data.cend(), 4);
+ EXPECT_EQ(*lower, 4);
+ // Lower bound includes the current element.
+ EXPECT_EQ(lower - data.cbegin(), 3);
 }
 
 TEST(upper_bound, ExampleOne) {
-
+ const std::vector<int> data{1,2,3,4,5,6,7,8,9,9,10};
+ const auto upper = std::upper_bound(data.cbegin(), data.cend(), 9);
+ EXPECT_EQ(*upper, 10);
+ // Upper bound goes one past the current element.
+ EXPECT_EQ(upper - data.cbegin(), 10);
 }
 
 TEST(binary_search, ExampleOne) {
+ const std::vector<int> data{1,2,3,4,5,6,7,8,9,9,10};
+ const bool found = std::binary_search(data.cbegin(), data.cend(), 3);
+ EXPECT_TRUE(found);
 
+ const bool not_found = std::binary_search(data.cbegin(), data.cend(), 11);
+ EXPECT_FALSE(not_found);
 }
 
 TEST(equal_range, ExampleOne) {
-
+ // This is useful when you want an upper and a lower bound.
+ const std::vector<int> data{1,2,3,3,4,4,5,5,5,6,7,8};
+ const auto [lower, upper] = std::equal_range(data.cbegin(), data.cend(), 5);
+ EXPECT_EQ(*lower, 5);
+ EXPECT_EQ(lower - data.cbegin(), 6);
+
+ EXPECT_EQ(*upper, 6);
+ EXPECT_EQ(upper - data.cbegin(), 9);
 }
 
 // Other operations (on sorted ranges).