Files
mercury/tests/term/mergesort_t.m
Zoltan Somogyi fdd141bf77 Clean up the tests in the other test directories.
tests/invalid/*.{m,err_exp}:
tests/misc_tests/*.m:
tests/mmc_make/*.m:
tests/par_conj/*.m:
tests/purity/*.m:
tests/stm/*.m:
tests/string_format/*.m:
tests/structure_reuse/*.m:
tests/submodules/*.m:
tests/tabling/*.m:
tests/term/*.m:
tests/trailing/*.m:
tests/typeclasses/*.m:
tests/valid/*.m:
tests/warnings/*.{m,exp}:
    Make these tests use four-space indentation, and ensure that
    each module is imported on its own line. (I intend to use the latter
    to figure out which subdirectories' tests can be executed in parallel.)

    These changes usually move code to different lines. For the tests
    that check compiler error messages, expect the new line numbers.

browser/cterm.m:
browser/tree234_cc.m:
    Import only one module per line.

tests/hard_coded/boyer.m:
    Fix something I missed.
2015-02-16 12:32:18 +11:00

64 lines
1.3 KiB
Mathematica

%---------------------------------------------------------------------------%
% vim: ts=4 sw=4 et ft=mercury
%---------------------------------------------------------------------------%
:- module mergesort_t.
:- interface.
:- type list(T)
---> []
; [T | list(T)].
:- pred mergesort(list(int)::in, list(int)::out) is nondet.
:- implementation.
:- import_module int.
mergesort([], []).
mergesort([X], [X]).
mergesort([X, Y | Xs], Ys) :-
split2([X, Y | Xs], X1s, X2s),
mergesort(X1s, Y1s),
mergesort(X2s, Y2s),
merge(Y1s, Y2s, Ys).
:- pred split(list(T), list(T), list(T)).
:- mode split(in, out, out).
split(Xs, Ys, Zs) :-
split0(Xs, Ys, Zs).
split(Xs, Ys, Zs) :-
split1(Xs, Ys, Zs).
split(Xs, Ys, Zs) :-
split2(Xs, Ys, Zs).
:- pred split0(list(T), list(T), list(T)).
:- mode split0(in, out, out).
split0([], [], []).
:- pred split1(list(T), list(T), list(T)).
:- mode split1(in, out, out).
split1([X], [X], []).
:- pred split2(list(T), list(T), list(T)).
:- mode split2(in, out, out).
split2([X, Y | Xs], [X | Ys], [Y | Zs]) :-
split(Xs, Ys, Zs).
:- pred merge(list(int), list(int), list(int)).
:- mode merge(in, in, out).
merge([], Xs, Xs).
merge(Xs, [], Xs).
merge([X | Xs], [Y | Ys], [X | Zs]) :-
X=<Y,
merge(Xs, [Y | Ys], Zs).
merge([X | Xs], [Y | Ys], [X | Zs]) :-
X>Y,
merge([X | Xs], Ys, Zs).