c - Array compare with memcmp vs element by element comparsion -


this question has answer here:

which implementation better , why?

element element comparison using loop or memcmp() implementation

int a[] = {1,2,3}; int b[] = {1,3,5};  memcmp(a, b, sizeof(int)*n)

or

 (i = 0; < n ; i++)     {        if (a[i] == b[i])         {             /* code */         }     }

memcmp faster: heavily optimized compiler use special instructions on cpu, loop unrolling, , other "advanced" techniques generated code simple loop (generally) won't use. however, memcmp can compare byte values; fine in case of array of integers, (probably) wouldn't work array of objects.


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