4 - q = realloc(p, (n)*(m))
5 + q = reallocarray(p, n, m)
9 - q = realloc(p, n*(m))
10 + q = reallocarray(p, n, m)
12 expression q, p, n, m;
14 - q = realloc(p, (n)*m)
15 + q = reallocarray(p, n, m)
17 expression q, p, n, m;
20 + q = reallocarray(p, n, m)