Is this the weirdest thing in C?
The article explains C programming's pointer and array indexing peculiarities, highlighting that x[i] and i[x] access the same memory address, despite i[x] being unconventional and discouraged.
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The article discusses some of the peculiarities of the C programming language, particularly focusing on the behavior of pointers and array indexing. It highlights the expression x[i] == i[x], which demonstrates that accessing an array element can be done in two seemingly different ways that yield the same result. This is due to the way arrays are treated in C, where the name of the array acts as a pointer to its first element. The author explains that both x[i] and i[x] access the same memory address, illustrating this with a simple code example. The output confirms that both expressions return the same value, although using i[x] is unconventional and not recommended in practice. The article concludes by acknowledging that while this may not be the weirdest aspect of C, it certainly exemplifies the language's quirks.
- C's array indexing allows for unconventional expressions like x[i] == i[x].
- Both expressions access the same memory address due to the commutative property of addition.
- The article provides a code example to illustrate this behavior.
- Using i[x] is discouraged despite it being functionally equivalent to x[i].
- The discussion highlights the challenges novice programmers face with C's pointer and memory management concepts.
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5 comments char*M,A,Z,E=40,J[40],T[40];main(C){for(*J=A=scanf(M="%d",&C);
-- E; J[ E] =T
[E ]= E) printf("._"); for(;(A-=Z=!Z) || (printf("\n|"
) , A = 39 ,C --
) ; Z || printf (M ))M[Z]=Z[A-(E =A[J-Z])&&!C
& A == T[ A]
|6<<27<rand()||!C&!Z?J[T[E]=T[A]]=E,J[T[A]=A-Z]=A,"_.":" |"];}
https://www.lysator.liu.se/c/duffs-device.html (the original, better description)
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