27 lines
727 B
C
27 lines
727 B
C
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#include <stdio.h>
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int RecursionHalfSearch(int a[], int left, int right, int key) {
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if (left <= right) {
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int middle = (left + right) / 2;
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if (key == a[middle])
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return middle;
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else if (key > a[middle])
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return RecursionHalfSearch(a, middle + 1, right, key);
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else
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return RecursionHalfSearch(a, left, middle - 1, key);
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} else {
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return -1;
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}
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}
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int main() {
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int a[] = {1, 3, 5, 7, 9};
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int size = sizeof(a) / sizeof(a[0]);
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int key = 7;
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int index = RecursionHalfSearch(a, 0, size - 1, key);
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if (index != -1)
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printf("Element found at index %d\n", index);
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else
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printf("Element not found\n");
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return 0;
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}
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