回答編集履歴
1
修正
answer
CHANGED
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@@ -5,15 +5,16 @@
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5
5
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#include <iterator>
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6
6
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#include <algorithm>
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7
7
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8
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+
int binary_search(const std::vector<int>& numbers, int target) {
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9
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auto itr = std::lower_bound(numbers.begin(), numbers.end(), 5);
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10
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return (itr == numbers.end() || *itr != 5) ?
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11
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-1 : static_cast<int>(std::distance(numbers.begin(), itr));
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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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int main(void) {
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15
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using namespace std;
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vector<int> numbers = { 1, 2 ,3 ,4 ,5 };
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11
17
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12
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-
auto itr = lower_bound(numbers.begin(), numbers.end(), 5);
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13
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-
if ( itr == numbers.end() || *itr != 5 ) {
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14
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cout << -1 << endl;
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15
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} else {
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16
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-
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18
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cout << binary_search(numbers, 5) << endl;
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17
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-
}
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}
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```
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