iframe-proxy | Sunbelt Computer Software

History

166 lines (144 loc) · 3.61 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

* <!--

* This program is distributed under

* the terms of the MIT license.

* Please see the LICENSE file for details.

* -->

* In the game of Towers of Hanoi, you have 3 rods and N disks of different

* sizes which can slide onto any tower. The puzzle starts with disks sorted in

* ascending order of size from top to bottom (each disk sits on top of an even

* larger disk) with the following constraints.

* 1. Only one disk can be moved at a time.

* 2. A disk is slid off the top of one rod onto the next rod.

* 3. A disk can only be placed on top of a larger disk.

* Write a program to move the disks from the first rod to the last.

/*____________________________________________________________________________*/

/**

* @class {public} Tower

* A data structure for a Hanoi tower.

/**

* @constructor Tower.Tower

* Creates a new tower.

* @param {Integer} i - the index of the tower.

function Tower(i) {

this.disks = [];

this.index = i;

}

var tp = Tower.prototype;

/**

* @function {public} Tower.add

* Add a disk to the tower.

* @param {Integer} d - the size of the disk.

tp.add = function(d) {

if (this.disks.length === 0 && this.disks[0] <= d) {

return;

}

this.disks.push(d);

};

/**

* @function {public} Tower.moveTopTo

* Moves the top disk of this tower, to another tower.

* @param {Tower} anotherTower - the tower to move to.

tp.moveTopTo = function(anotherTower) {

var top = this.disks.pop();

anotherTower.add(top);

console.log([

'Moved disk ', top, ' from ', this.index, ' to ', anotherTower.index

].join(''));

};

/**

* @function {public} Tower.print

* Prints the contents of the tower.

tp.print = function() {

console.log(['Contents of tower', this.index].join(''));

var i = 0;

var buffer = [];

for (i = this.disks.length - 1; i >= 0; i--) {

buffer.push(' ');

buffer.push(this.disks[i]);

}

console.log(buffer.join(''));

}

/**

* @function {public} Tower.moveDisks

* Moves n disks from ths tower to destination tower using a buffer tower.

* @param {Integer} n - the number of disks to move.

* @param {Tower} destination - the destination `Tower` to move to.

* @param {Tower} buffer - intermediate buffer `Tower`.

tp.moveDisks = function(n, destination, buffer) {

if (n === 0) {

return;

}

this.moveDisks(n - 1, buffer, destination);

this.moveTopTo(destination);

buffer.moveDisks(n-1, destination, this);

};

(function main() {

var n = 5;

var towers = [];

var i = 0;

for (i = 0; i < 3; i++) {

towers[i] = new Tower(i);

}

for (i = n -1; i >= 0; i--) {

towers[0].add(i);

}

towers[0].moveDisks(n, towers[2], towers[1]);

towers[2].print();

}());

Output: ($ /usr/bin/node 009.js)

Moved disk 0 from 0 to 2

Moved disk 1 from 0 to 1

Moved disk 0 from 2 to 1

Moved disk 2 from 0 to 2

Moved disk 0 from 1 to 0

Moved disk 1 from 1 to 2

Moved disk 0 from 0 to 2

Moved disk 3 from 0 to 1

Moved disk 0 from 2 to 1

Moved disk 1 from 2 to 0

Moved disk 0 from 1 to 0

Moved disk 2 from 2 to 1

Moved disk 0 from 0 to 2

Moved disk 1 from 0 to 1

Moved disk 0 from 2 to 1

Moved disk 4 from 0 to 2

Moved disk 0 from 1 to 0

Moved disk 1 from 1 to 2

Moved disk 0 from 0 to 2

Moved disk 2 from 1 to 0

Moved disk 0 from 2 to 1

Moved disk 1 from 2 to 0

Moved disk 0 from 1 to 0

Moved disk 3 from 1 to 2

Moved disk 0 from 0 to 2

Moved disk 1 from 0 to 1

Moved disk 0 from 2 to 1

Moved disk 2 from 0 to 2

Moved disk 0 from 1 to 0

Moved disk 1 from 1 to 2

Moved disk 0 from 0 to 2

Contents of tower2

0 1 2 3 4

Sunbelt Computer Software

PL/B Language Development and Support

Navigation Menu

Uh oh!

Sunbelt Computer Software

PL/B Language Development and Support

Uh oh!

FilesExpand file tree

009.js

Latest commit

History

009.js

File metadata and controls