質問編集履歴
2
longest_collatz関数を追加
test
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File without changes
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test
CHANGED
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@@ -7,6 +7,66 @@
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7
7
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8
8
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9
9
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```
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10
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+
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11
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+
std::pair<unsigned long long, long> longest_collatz(unsigned long long const limit)
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12
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+
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13
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{
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14
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15
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long length = 0;
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unsigned long long number = 0;
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18
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20
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std::vector<int> cache(limit + 1, 0);
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22
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+
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23
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for (unsigned long long i = 2; i <= limit; i++)
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26
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+
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27
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{
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28
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29
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auto n = i;
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30
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31
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long steps = 0;
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32
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33
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while (n != 1 && n >= i)
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34
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+
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35
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{
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36
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+
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37
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if ((n % 2) == 0)
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38
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+
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39
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n = n / 2;
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40
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+
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41
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else
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42
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43
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n = n * 3 + 1;
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44
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+
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45
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steps++;
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46
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+
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47
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}
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48
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+
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49
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+
cache[i] = steps + cache[n];
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50
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+
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51
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+
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52
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+
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53
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if (cache[i] > length)
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54
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+
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55
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+
{
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56
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+
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57
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length = cache[i];
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58
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+
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59
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number = i;
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60
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+
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61
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}
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62
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+
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63
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}
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64
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+
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65
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+
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66
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+
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67
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+
return std::make_pair(number, length);
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68
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+
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69
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+
}
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10
70
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11
71
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int main()
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12
72
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1
d.stepをd.stepsに修正
test
CHANGED
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File without changes
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test
CHANGED
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@@ -2,7 +2,7 @@
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2
2
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3
3
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if (result.first != d.start || result.second != d.steps)
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4
4
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5
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-
のd.stepはどういう意味ですか？
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5
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+
のd.stepsはどういう意味ですか？
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6
6
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7
7
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8
8
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