add Integer.random function

js/module/data/array2d.js

 'use strict';
 
+const Integer = require('./integer');
+
 const random = (N, M, min, max) => {
   if (!N) N = 10;
   if (!M) M = 10;
@@ -9,7 +11,7 @@ const random = (N, M, min, max) => {
   for (var i = 0; i < N; i++) {
     D.push([]);
     for (var j = 0; j < M; j++) {
-      D[i].push((Math.random() * (max - min + 1) | 0) + min);
+      D[i].push(Integer.random(min, max));
     }
   }
   return D;

js/module/data/coordinate_system.js

 'use strict';
 
+const Integer = require('./integer');
+
 const random = (N, min, max) => {
   if (!N) N = 7;
   if (!min) min = 1;
@@ -8,7 +10,7 @@ const random = (N, min, max) => {
   for (var i = 0; i < N; i++) C[i] = new Array(2);
   for (var i = 0; i < N; i++)
     for (var j = 0; j < C[i].length; j++)
-      C[i][j] = (Math.random() * (max - min + 1) | 0) + min;
+      C[i][j] = Integer.random(min, max);
   return C;
 };
 

js/module/data/index.js

 'use strict';
 
+const Integer = require('./integer');
 const Array1D = require('./array1d');
 const Array2D = require('./array2d');
 const CoordinateSystem = require('./coordinate_system');
@@ -9,6 +10,7 @@ const WeightedDirectedGraph = require('./weighted_directed_graph');
 const WeightedUndirectedGraph = require('./weighted_undirected_graph');
 
 module.exports = {
+  Integer,
   Array1D,
   Array2D,
   CoordinateSystem,

js/module/data/integer.js

+'use strict';
+
+const random = (min, max) => {
+  return (Math.random() * (max - min + 1) | 0) + min;
+};
+
+module.exports = {
+  random
+};

js/module/data/weighted_directed_graph.js

 'use strict';
 
+const Integer = require('./integer');
+
 const random = (N, ratio, min, max) => {
   if (!N) N = 5;
   if (!ratio) ratio = .3;
@@ -10,7 +12,7 @@ const random = (N, ratio, min, max) => {
     G[i] = new Array(N);
     for (var j = 0; j < N; j++) {
       if (i != j && (Math.random() * (1 / ratio) | 0) == 0) {
-        G[i][j] = (Math.random() * (max - min + 1) | 0) + min;
+        G[i][j] = Integer.random(min, max);
       }
     }
   }

js/module/data/weighted_undirected_graph.js

 'use strict';
 
+const Integer = require('./integer');
+
 const random = (N, ratio, min, max) => {
   if (!N) N = 5;
   if (!ratio) ratio = .3;
@@ -10,7 +12,7 @@ const random = (N, ratio, min, max) => {
   for (var i = 0; i < N; i++) {
     for (var j = 0; j < N; j++) {
       if (i > j && (Math.random() * (1 / ratio) | 0) == 0) {
-        G[i][j] = G[j][i] = (Math.random() * (max - min + 1) | 0) + min;
+        G[i][j] = G[j][i] = Integer.random(min, max);
       }
     }
   }