lrange(a, b) := makelist(i, i, a, b)$

suffixify(n) := block(
    suffixes: ["'st", "'nd", "'rd"],
    lastd: mod(n, 10),
    last2d: mod(n, 100),
    sflag: member(lastd, lrange(1, 3)),
    suffix: if sflag and last2d#10+lastd then suffixes[lastd] else "'th",
    sconcat(n, suffix)
)$

test_nums: append(lrange(0, 25), lrange(250, 265), lrange(1000, 1025))$
map(suffixify, test_nums);