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C



#include <stdio.h>

#include <string.h>

#include <alloc.h>
#define NINSU 5
typedef struct

{

    char  name[20];

    int   height;

    float weight;

} gstudent;
typedef

    int (*compare)(gstudent*, gstudent*);
int compare_height(gstudent* x, gstudent* y)

{

    if (x->height > y->height) return  1;

    if (x->height < y->height) return -1;

    return 0;

}

int compare_weight(gstudent* x, gstudent* y)

{

    if (x->weight > y->weight) return  1;

    if (x->weight < y->weight) return -1;

    return 0;

}
void swap(gstudent** x, gstudent** y)

{

    gstudent* tmp = *x;

    *x = *y;

    *y = tmp;

}
void sort(gstudent* data, gstudent** ptr, int n, compare comp)

{

    int k = n - 1;

    while (k >= 0)

    {

        int i, j;

        for (i = 1, j = -1; i <= k; i++)

        {

            if (comp(ptr[i - 1], ptr[i]) > 0)

            {

                j = i - 1;

                swap(&ptr[i], &ptr[j]);

            }

        }

        k = j;

    }

}
void set_student(gstudent* std, char name[], int height, float weight)

{

    strcpy(std->name, name);

    std->height = height;

    std->weight = weight;

}
int main(int argc, char* argv[])

{

    int i;

    gstudent* data;

    data = (gstudent*)malloc(sizeof(gstudent) * 5);
    gstudent** ptr;

    ptr = (gstudent**)malloc(sizeof(gstudent*) * 5);
    set_student(&data[0], "Sato",    178, 61.0);

    set_student(&data[1], "Sanaka",  175, 60.5);

    set_student(&data[2], "Takao",   173, 80.0);

    set_student(&data[3], "Mike",    165, 72.0);

    set_student(&data[4], "Masaki",  179, 77.5);
    for (i = 0; i < NINSU; i++)

        ptr[i] = &data[i];
    puts("ソート前：");

    for (i = 0; i < NINSU; i++)

        printf("%2d:%-8s%4d%6.1f\n", i + 1, ptr[i]->name, ptr[i]->height, ptr[i]->weight);

    puts("");
    /* 身長でソート */

    sort(data, ptr, NINSU, &compare_height);
    puts("身長でソート後：");

    for (i = 0; i < NINSU; i++)

        printf("%2d:%-8s%4d%6.1f\n", i + 1, ptr[i]->name, ptr[i]->height, ptr[i]->weight);

    puts("");
    /* 体重でソート */

    sort(data, ptr, NINSU, &compare_weight);
    puts("体重でソート後：");

    for (i = 0; i < NINSU; i++)

        printf("%2d:%-8s%4d%6.1f\n", i + 1, ptr[i]->name, ptr[i]->height, ptr[i]->weight);
    free(data);

    free(ptr);
    return 0;

}

実行結果

R:\>lesson100\project1.exe
ソート前：
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5

身長でソート後：
1:Mike 165 72.0
2:Takao 173 80.0
3:Sanaka 175 60.5
4:Sato 178 61.0
5:Masaki 179 77.5

体重でソート後：
1:Sanaka 175 60.5
2:Sato 178 61.0
3:Mike 165 72.0
4:Masaki 179 77.5
5:Takao 173 80.0

C++



#include <stdio.h>

#include <string.h>

#include <alloc.h>
const int NINSU = 5;
struct gstudent

{

    char  name[20];

    int   height;

    float weight;

};
typedef

    int (*compare)(gstudent*, gstudent*);
int compare_height(gstudent* x, gstudent* y)

{

    if (x->height > y->height) return  1;

    if (x->height < y->height) return -1;

    return 0;

}

int compare_weight(gstudent* x, gstudent* y)

{

    if (x->weight > y->weight) return  1;

    if (x->weight < y->weight) return -1;

    return 0;

}
void swap(gstudent** x, gstudent** y)

{

    gstudent* tmp = *x;

    *x = *y;

    *y = tmp;

}
void sort(gstudent* data, gstudent** ptr, int n, compare comp)

{

    int k = n - 1;

    while (k >= 0)

    {

        int i, j;

        for (i = 1, j = -1; i <= k; i++)

        {

            if (comp(ptr[i - 1], ptr[i]) > 0)

            {

                j = i - 1;

                swap(&ptr[i], &ptr[j]);

            }

        }

        k = j;

    }

}
void set_student(gstudent* std, char name[], int height, float weight)

{

    strcpy(std->name, name);

    std->height = height;

    std->weight = weight;

}
int main(int argc, char* argv[])

{

    int i;

    gstudent*  data = new gstudent[5];

    gstudent** ptr  = new gstudent*[5];
    set_student(&data[0], "Sato",    178, 61.0);

    set_student(&data[1], "Sanaka",  175, 60.5);

    set_student(&data[2], "Takao",   173, 80.0);

    set_student(&data[3], "Mike",    165, 72.0);

    set_student(&data[4], "Masaki",  179, 77.5);
    for (i = 0; i < NINSU; i++)

        ptr[i] = &data[i];
    puts("ソート前：");

    for (i = 0; i < NINSU; i++)

        printf("%2d:%-8s%4d%6.1f\n", i + 1, ptr[i]->name, ptr[i]->height, ptr[i]->weight);

    puts("");
    // 身長でソート

    sort(data, ptr, NINSU, &compare_height);
    puts("身長でソート後：");

    for (i = 0; i < NINSU; i++)

        printf("%2d:%-8s%4d%6.1f\n", i + 1, ptr[i]->name, ptr[i]->height, ptr[i]->weight);

    puts("");
    // 体重でソート

    sort(data, ptr, NINSU, &compare_weight);
    puts("体重でソート後：");

    for (i = 0; i < NINSU; i++)

        printf("%2d:%-8s%4d%6.1f\n", i + 1, ptr[i]->name, ptr[i]->height, ptr[i]->weight);
    delete[] data;

    delete[] ptr;
    return 0;

}

実行結果

T:\>lesson100\project1.exe
ソート前：
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5

身長でソート後：
1:Mike 165 72.0
2:Takao 173 80.0
3:Sanaka 175 60.5
4:Sato 178 61.0
5:Masaki 179 77.5

体重でソート後：
1:Sanaka 175 60.5
2:Sato 178 61.0
3:Mike 165 72.0
4:Masaki 179 77.5
5:Takao 173 80.0

Delphi



program Project1;
{$APPTYPE CONSOLE}
uses

    SysUtils;
const

    NINSU = 5;
type

    TStudent = record

        name:   array[0..19] of Char;

        height: Integer;

        weight: Real;

    end;
    PStudent   = ^TStudent;

    TCharArray = array[0..19] of Char;
    TCompare = function (x:TStudent; y:TStudent):Integer;
function compare_height(x:TStudent; y:TStudent):Integer;

begin

    if      (x.height > y.height) then result :=  1

    else if (x.height < y.height) then result := -1

    else                               result :=  0;

end;
function compare_weight(x:TStudent; y:TStudent):Integer;

begin

    if      (x.weight > y.weight) then result :=  1

    else if (x.weight < y.weight) then result := -1

    else                               result :=  0;

end;
procedure swap(var x:PStudent; var y:PStudent);

var

    tmp: PStudent;

begin

    tmp:= x;

    x  := y;

    y  := tmp;

end;
procedure sort(var ptr:array of PStudent; n:Integer; Comp:TCompare);

var

    i, j, k: Integer;

begin

    k := 4;

    while (k >= 0) do

    begin

        j := -1;

        for i := 1 to k do

        begin

            if (Comp(ptr[i - 1]^, ptr[i]^) > 0) then

            begin

                j := i - 1;

                swap(ptr[i], ptr[j]);

            end;

        end;

        k := j;

    end;

end;
procedure set_student(var data:TStudent; name:String; height:Integer; weight:Real);

begin

    StrCopy(data.name, PChar(name));

    data.height := height;

    data.weight := weight;

end;
procedure main();

var

    i:Integer;

    data: array of TStudent;

    ptr:  array of PStudent;

begin

    GetMem(data, SizeOf(TStudent) * 3);

    GetMem(ptr,  SizeOf(PStudent) * 3);

    set_student(data[0], 'Sato',    178, 61.0);

    set_student(data[1], 'Sanaka',  175, 60.5);

    set_student(data[2], 'Takao',   173, 80.0);
    ReallocMem(data, SizeOf(TStudent) * 5);

    ReallocMem(ptr,  SizeOf(PStudent) * 5);

    set_student(data[3], 'Mike',    165, 72.0);

    set_student(data[4], 'Masaki',  179, 77.5);
    for i := 0 to 4 do

        ptr[i] := @data[i];
    Writeln('ソート前：');

    for i := 0 to 4 do

        Writeln(Format('%2d:%-8s%4d%6.1f', [i + 1, data[i].name, data[i].height, data[i].weight]));

    Writeln('');
    (* 身長でソート *)

    sort(ptr, NINSU, compare_height);
    Writeln('身長でソート後：');

    for i := 0 to 4 do

        Writeln(Format('%2d:%-8s%4d%6.1f', [i + 1, ptr[i]^.name, ptr[i]^.height, ptr[i]^.weight]));

    Writeln('');
    (* 体重でソート *)

    sort(ptr, NINSU, compare_weight);
    Writeln('体重でソート後：');

    for i := 0 to 4 do

        Writeln(Format('%2d:%-8s%4d%6.1f', [i + 1, ptr[i]^.name, ptr[i]^.height, ptr[i]^.weight]));
    FreeMem(data);

    FreeMem(ptr);

end;
begin

    main;

end.

実行結果

S:\>lesson100\project1.exe
ソート前：
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5

身長でソート後：
1:Mike 165 72.0
2:Takao 173 80.0
3:Sanaka 175 60.5
4:Sato 178 61.0
5:Masaki 179 77.5

体重でソート後：
1:Sanaka 175 60.5
2:Sato 178 61.0
3:Mike 165 72.0
4:Masaki 179 77.5
5:Takao 173 80.0

Perl

$NINSU = 5;

sub swap
{
    my ($x, $y) = @_;
    
    $tmp = $$x;
    $$x  = $$y;
    $$y  = $tmp;
}

sub compare_height
{
    my ($x, $y) = @_;

    return  1 if ($$x->{"height"} > $$y->{"height"});
    return -1 if ($$x->{"height"} < $$y->{"height"});
    return 0;
}

sub compare_weight
{
    my ($x, $y) = @_;

    return  1 if ($$x->{"weight"} > $$y->{"weight"});
    return -1 if ($$x->{"weight"} < $$y->{"weight"});
    return 0;
}

sub sort
{
    my ($data, $ptr, $n, $compare) = @_;
    
    $k = $$n - 1;
    while ($k >= 0)
    {
        $j = -1;
        foreach $i(1..$k)
        {
            if ($compare->(\$$data[$ptr[$i - 1]], \$$data[$ptr[$i]]) > 0)
            {
                $j = $i - 1;
                &swap(\$$ptr[$i], \$$ptr[$j]);
            }
        }
        $k = $j;
    }
}


@data = ();
push(@data, {name => "Sato",   height => 178, weight => 61.0});
push(@data, {name => "Sanaka", height => 175, weight => 60.5});
push(@data, {name => "Takao",  height => 173, weight => 80.0});
push(@data, {name => "Mike",   height => 165, weight => 72.0});
push(@data, {name => "Masaki", height => 179, weight => 77.5});

@ptr = (0..4);

print "ソ\ート前：\n";
for (0..$NINSU-1)
{
    printf("%2d:%-8s%4d%6.1f\n", $_ + 1, $data[$ptr[$_]]{"name"}, $data[$ptr[$_]]{"height"}, $data[$ptr[$_]]{"weight"});

}
print "\n";

&sort(\@data, \@ptr, \$NINSU, \&compare_height);

print "身長でソ\ート後：\n";
for (0..$NINSU-1)
{
    printf("%2d:%-8s%4d%6.1f\n", $_ + 1, $data[$ptr[$_]]{"name"}, $data[$ptr[$_]]{"height"}, $data[$ptr[$_]]{"weight"});
}
print "\n";

&sort(\@data, \@ptr, \$NINSU, \&compare_weight);

print "体重でソ\ート後：\n";
for (0..$NINSU-1)
{
    printf("%2d:%-8s%4d%6.1f\n", $_ + 1, $data[$ptr[$_]]{"name"}, $data[$ptr[$_]]{"height"}, $data[$ptr[$_]]{"weight"});
}
print "\n";

print "元の配列：\n";
$i = 1;
map { printf("%2d:%-8s%4d%6.1f\n", $i, $_->{"name"}, $_->{"height"}, $_->{"weight"}); $i++; } @data;

実行結果

L:\>perl lesson_12_100.pl
ソート前：
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5

身長でソート後：
1:Mike 165 72.0
2:Takao 173 80.0
3:Sanaka 175 60.5
4:Sato 178 61.0
5:Masaki 179 77.5

体重でソート後：
1:Sanaka 175 60.5
2:Sato 178 61.0
3:Mike 165 72.0
4:Masaki 179 77.5
5:Takao 173 80.0

元の配列：
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5

Ruby

NINSU = 5

def compare_height(x, y)
    return  1 if (x["height"] > y["height"])
    return -1 if (x["height"] < y["height"])
    return 0
end

def compare_weight(x, y)
    return  1 if (x["weight"] > y["weight"])
    return -1 if (x["weight"] < y["weight"])
    return 0
end

def sort(data, ptr, n, compare)
    k = n - 1
    while (k >= 0)
        j = -1
        for i in 1..k
            if (compare.call(data[ptr[i-1]], data[ptr[i]]) > 0)
                j = i - 1
                ptr[i], ptr[j] = ptr[j], ptr[i]
            end
        end
        k = j
    end
end

data = []
data.push({"name" => "Sato",   "height" => 178, "weight" => 61.0})
data.push({"name" => "Sanaka", "height" => 175, "weight" => 60.5})
data.push({"name" => "Takao",  "height" => 173, "weight" => 80.0})
data.push({"name" => "Mike",   "height" => 165, "weight" => 72.0})
data.push({"name" => "Masaki", "height" => 179, "weight" => 77.5})

ptr = [0, 1, 2, 3, 4]

puts "ソ\ート前："
data.each_with_index do |d, i|
    printf("%2d:%-8s%4d%6.1f\n", i + 1, d["name"], d["height"], d["weight"])
end
puts ""

sort(data, ptr, NINSU, method(:compare_height))

puts "身長でソ\ート後："
ptr.each_with_index do |p, i|
    printf("%2d:%-8s%4d%6.1f\n", i + 1, data[p]["name"], data[p]["height"], data[p]["weight"])
end
puts ""

sort(data, ptr, NINSU, method(:compare_weight))

puts "体重でソ\ート後："
ptr.each_with_index do |p, i|
    printf("%2d:%-8s%4d%6.1f\n", i + 1, data[p]["name"], data[p]["height"], data[p]["weight"])
end
puts ""

puts "元の配列："
i = 1
data.map { |d| printf("%2d:%-8s%4d%6.1f\n", i, d["name"], d["height"], d["weight"]); i += 1 }

実行結果

L:\>ruby l:\lesson_12_100.rb
ソート前：
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5

身長でソート後：
1:Mike 165 72.0
2:Takao 173 80.0
3:Sanaka 175 60.5
4:Sato 178 61.0
5:Masaki 179 77.5

体重でソート後：
1:Sanaka 175 60.5
2:Sato 178 61.0
3:Mike 165 72.0
4:Masaki 179 77.5
5:Takao 173 80.0

元の配列：
1:Sato 178 61.0
2:Sanaka 175 60.5
3:Takao 173 80.0
4:Mike 165 72.0
5:Masaki 179 77.5