/
069_MedianStream.cpp
126 lines (98 loc) · 2.67 KB
/
069_MedianStream.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
// Coding Interviews: Questions, Analysis & Solutions
// Harry He
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <functional>
using namespace std;
template<typename T> class DynamicArray
{
public:
void Insert(T num)
{
if(((minHeap.size() + maxHeap.size()) & 1) == 0)
{
if(maxHeap.size() > 0 && num < maxHeap[0])
{
maxHeap.push_back(num);
push_heap(maxHeap.begin(), maxHeap.end(), less<T>());
num = maxHeap[0];
pop_heap(maxHeap.begin(), maxHeap.end(), less<T>());
maxHeap.pop_back();
}
minHeap.push_back(num);
push_heap(minHeap.begin(), minHeap.end(), greater<T>());
}
else
{
if(minHeap.size() > 0 && minHeap[0] < num)
{
minHeap.push_back(num);
push_heap(minHeap.begin(), minHeap.end(), greater<T>());
num = minHeap[0];
pop_heap(minHeap.begin(), minHeap.end(), greater<T>());
minHeap.pop_back();
}
maxHeap.push_back(num);
push_heap(maxHeap.begin(), maxHeap.end(), less<T>());
}
}
int GetMedian()
{
int size = minHeap.size() + maxHeap.size();
if(size == 0)
throw exception("No numbers are available");
T median = 0;
if(size & 1 == 1)
median = minHeap[0];
else
median = (minHeap[0] + maxHeap[0]) / 2;
return median;
}
private:
vector<T> minHeap;
vector<T> maxHeap;
};
// ==================== Test Code ====================
void Test(char* testName, DynamicArray<double>& numbers, double expected)
{
if(testName != NULL)
printf("%s begins: ", testName);
if(abs(numbers.GetMedian() - expected) < 0.0000001)
printf("Passed.\n");
else
printf("FAILED.\n");
}
int main(int argc, char* argv[])
{
DynamicArray<double> numbers;
printf("Test1 begins: ");
try
{
numbers.GetMedian();
printf("FAILED.\n");
}
catch(exception e)
{
printf("Passed.\n");
}
numbers.Insert(5);
Test("Test2", numbers, 5);
numbers.Insert(2);
Test("Test3", numbers, 3.5);
numbers.Insert(3);
Test("Test4", numbers, 3);
numbers.Insert(4);
Test("Test6", numbers, 3.5);
numbers.Insert(1);
Test("Test5", numbers, 3);
numbers.Insert(6);
Test("Test7", numbers, 3.5);
numbers.Insert(7);
Test("Test8", numbers, 4);
numbers.Insert(0);
Test("Test9", numbers, 3.5);
numbers.Insert(8);
Test("Test10", numbers, 4);
return 0;
}