23 lines
479 B
C
23 lines
479 B
C
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#include <stdio.h>
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int main()
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{
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char arr[64] = "hi, disen!";
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// 实现 strlen() 的功能, 统计字符串的长度
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int i = 0;
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while (arr[i])
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i++;
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printf("%s length: %d\n", arr, i);
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// 反转字符串
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int j = 0;
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int mid = i >> 1; // 含义: i / 2, 位运算更快
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while (j < mid)
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{
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arr[j] ^= arr[i - j - 1];
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arr[i - j - 1] ^= arr[j];
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arr[j] ^= arr[i - j - 1];
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j++;
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}
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printf("%s\n", arr);
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}
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