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Obviously, there is a relationship between array subscripts [] and pointers. The expression dis[i] is equivalent to *(dis+i) for all integral values of i. In other words, if dis is an array object (equivalently, a pointer to the initial element of an array object) and i is an integer, dis[i] designates the ith element of dis. In fact, because *(dis+i) can be expressed as *(i+dis), the expression dis[i] can be represented as i[dis], although doing so is not encouraged. Since Because array indices are zero-based, the first element is designated as dis[0], or equivalently as *(dis+0) or simply *dis.
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