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29 lines
525 B
C
29 lines
525 B
C
//这是我能理解的格式
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int mystrcmp(char* str1, char* str2) {
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int ret = 0;
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while ((ret = ((unsigned char)*str1 - (unsigned char)*str2)) == 0 && *str1) {
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++str1, ++str2;
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}
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return ret;
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}
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//原版在这里
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int __cdecl strcmp(
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const char* src,
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const char* dst
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)
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{
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int ret = 0;
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while ((ret = *(unsigned char*)src - *(unsigned char*)dst) == 0 && *dst)
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{
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++src, ++dst;
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}
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//这里不太理解，那个大神理解了可以给我讲一下，谢谢
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return ((-ret) < 0) - (ret < 0); // (if positive) - (if negative) generates branchless code
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} |