AceCommon  1.4.5
Arduino library for low-level common functions and features with no external dependencies
isSorted.h
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2 MIT License
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4 Copyright (c) 2021 Brian T. Park
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24 
32 #ifndef ACE_COMMON_IS_SORTED_H
33 #define ACE_COMMON_IS_SORTED_H
34 
35 namespace ace_common {
36 
58 template <typename K>
59 bool isSortedByKey(size_t size, K&& key) {
60  if (size == 0) return false;
61 
62  auto prev = key(0);
63  for (size_t i = 1; i < size; ++i) {
64  auto current = key(i);
65  if (current < prev) return false;
66  prev = current;
67  }
68  return true;
69 }
70 
83 template<typename X>
84 bool isSorted(const X list[], size_t size) {
85  if (size == 0) return false;
86 
87  auto prev = list[0];
88  for (size_t i = 1; i < size; ++i) {
89  auto current = list[i];
90  if (current < prev) return false;
91  prev = current;
92  }
93  return true;
94 
95 #if 0
96  // This shorter alternative runs a lot slower on many platforms because the
97  // compiler is not able to optimize away the lambda expression and so the
98  // isSortedByKey() makes a function call on each iteration.
99  return isSortedByKey(size,
100  [&list](size_t i) { return list[i]; } /*key*/);
101 #endif
102 }
103 
104 } // ace_common
105 
106 #endif
ace_common::isSorted
bool isSorted(const X list[], size_t size)
Simplified version of isSortedByKey() where the elements of the array and the type returned by the ke...
Definition: isSorted.h:84
ace_common::isSortedByKey
bool isSortedByKey(size_t size, K &&key)
Determine if the abstract array is sorted according to its 'key'.
Definition: isSorted.h:59