-
Notifications
You must be signed in to change notification settings - Fork 0
/
day 82
113 lines (96 loc) · 2.65 KB
/
day 82
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
#include <iostream>
#include <string>
// convert valid roman numbers to binary numbers
unsigned int roman2number(const std::string& roman)
{
unsigned int result = 0;
// remember the value of the previous Roman letter
unsigned int last = 0;
// true, if the current letter is subtracted (and the next identical letters)
bool subtract = false;
// walk through the whole string from the end to the beginning ...
for (auto i = roman.rbegin(); i != roman.rend(); i++)
{
unsigned int current = 0;
switch (*i)
{
case 'M': current = 1000; break;
case 'D': current = 500; break;
case 'C': current = 100; break;
case 'L': current = 50; break;
case 'X': current = 10; break;
case 'V': current = 5; break;
case 'I': current = 1; break;
}
// smaller than its right neighbor ? => we must subtract
if (current < last)
{
subtract = true;
last = current;
}
// bigger than its right neighbor ? => we must add
else if (current > last)
{
subtract = false;
last = current;
}
// note: if current == last then we keep the variables "subtract" and "last" in their current state
// add/subtract accordingly
if (subtract)
result -= current;
else
result += current;
}
return result;
}
std::string number2roman(unsigned int number)
{
// apply these rules in the presented order:
// - as long as number >= steps[i] add roman[i] to result
const unsigned int NumRules = 13;
const unsigned int rules[NumRules] =
{ 1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1 };
const char* action[NumRules] =
{ "M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I" };
// apply all rules ...
std::string result;
for (unsigned int i = 0; i < NumRules; i++)
// ... as often as needed
while (number >= rules[i])
{
// reduce integer
number -= rules[i];
// add letter(s)
result += action[i];
}
return result;
}
int main()
{
// letters saved by optimization
unsigned int saved = 0;
unsigned int tests = 1000;
//#define ORIGINAL
#ifndef ORIGINAL
std::cin >> tests;
#endif
while (tests--)
{
// read Roman number
std::string roman;
std::cin >> roman;
// convert it to an integer and back to an optimal Roman number
auto number = roman2number(roman);
auto optimized = number2roman(number);
// count how many character were saved
saved += roman.size() - optimized.size();
#ifndef ORIGINAL
// print Roman number
std::cout << optimized << std::endl;
#endif
}
#ifdef ORIGINAL
std::cout << saved << std::endl;
#endif
return 0;
}