46 lines
1 KiB
C
46 lines
1 KiB
C
#include <stdio.h>
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#define MAXN 2000000
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int RecurBinarySearch(int a[], int key, int left, int right);
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int main() {
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int a
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[MAXN]; //这个数组比较大，如果在你的电脑中无法分配这么大的内存，请改小后测试。
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int n, m, i, key;
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scanf("%d %d", &n, &m);
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for (i = 0; i < n; i++)
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scanf("%d", &a[i]);
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for (i = 0; i < m; i++) {
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scanf("%d", &key);
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printf("%d", RecurBinarySearch(a, key, 0, n - 1));
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if (i != m - 1)
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printf(" ");
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else
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printf("\n");
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}
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return 0;
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}
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/* 请在这里填写答案 */
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// --last hope--
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#pragma GCC optimize("Ofast,inline") // "Ofast" = "O3,fast-math,allow-store-data-races,no-protect-parens"
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int RecurBinarySearch(int a[], int key, int left, int right) {
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if (left <= right) {
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int mid = (left + right) >> 1;
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if (a[mid] == key) { // Base case
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return mid;
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} else if (a[mid] > key) {
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// Search left
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return RecurBinarySearch(a, key, left, mid - 1);
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} else {
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return RecurBinarySearch(a, key, mid + 1, right);
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}
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} else {
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return -1;
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}
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}
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