refactor 399

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_399.java

@@ -30,62 +30,67 @@
  */
 public class _399 {
 
-    /**Credit: https://discuss.leetcode.com/topic/59146/java-ac-solution-using-graph
-     *
-     * Image a/b = k as a link between node a and b, the weight from a to b is k, the reverse link is 1/k. Query is to find a path between two nodes.*/
-    public double[] calcEquation(String[][] equations, double[] values, String[][] queries) {
-        Map<String, List<String>> pairs = new HashMap<>();
-        Map<String, List<Double>> valuePairs = new HashMap<>();
-        for (int i = 0; i < equations.length; i++) {
-            String[] equation = equations[i];
-            if (!pairs.containsKey(equation[0])) {
-                pairs.put(equation[0], new ArrayList<>());
-                valuePairs.put(equation[0], new ArrayList<>());
+    public static class Solution1 {
+        /**
+         * Credit: https://discuss.leetcode.com/topic/59146/java-ac-solution-using-graph
+         *
+         * Image a/b = k as a link between node a and b, the weight from a to b is k, the reverse link
+         * is 1/k. Query is to find a path between two nodes.
+         */
+        public double[] calcEquation(String[][] equations, double[] values, String[][] queries) {
+            Map<String, List<String>> pairs = new HashMap<>();
+            Map<String, List<Double>> valuePairs = new HashMap<>();
+            for (int i = 0; i < equations.length; i++) {
+                String[] equation = equations[i];
+                if (!pairs.containsKey(equation[0])) {
+                    pairs.put(equation[0], new ArrayList<>());
+                    valuePairs.put(equation[0], new ArrayList<>());
+                }
+                if (!pairs.containsKey(equation[1])) {
+                    pairs.put(equation[1], new ArrayList<>());
+                    valuePairs.put(equation[1], new ArrayList<>());
+                }
+                pairs.get(equation[0]).add(equation[1]);
+                pairs.get(equation[1]).add(equation[0]);
+                valuePairs.get(equation[0]).add(values[i]);
+                valuePairs.get(equation[1]).add(1 / values[i]);
             }
-            if (!pairs.containsKey(equation[1])) {
-                pairs.put(equation[1], new ArrayList<>());
-                valuePairs.put(equation[1], new ArrayList<>());
-            }
-            pairs.get(equation[0]).add(equation[1]);
-            pairs.get(equation[1]).add(equation[0]);
-            valuePairs.get(equation[0]).add(values[i]);
-            valuePairs.get(equation[1]).add(1 / values[i]);
-        }
 
-        double[] result = new double[queries.length];
-        for (int i = 0; i < queries.length; i++) {
-            String[] query = queries[i];
-            result[i] = dfs(query[0], query[1], pairs, valuePairs, new HashSet<>(), 1.0);
-            if (result[i] == 0.0) {
-                result[i] = -1.0;
+            double[] result = new double[queries.length];
+            for (int i = 0; i < queries.length; i++) {
+                String[] query = queries[i];
+                result[i] = dfs(query[0], query[1], pairs, valuePairs, new HashSet<>(), 1.0);
+                if (result[i] == 0.0) {
+                    result[i] = -1.0;
+                }
             }
+            return result;
         }
-        return result;
-    }
 
-    private double dfs(String start, String end, Map<String, List<String>> pairs, Map<String, List<Double>> valuePairs, HashSet<String> set, double value) {
-        if (set.contains(start)) {
-            return 0.0;
-        }
-        if (!pairs.containsKey(start)) {
-            return 0.0;
-        }
-        if (start.equals(end)) {
-            return value;
-        }
-        set.add(start);
+        private double dfs(String start, String end, Map<String, List<String>> pairs,
+            Map<String, List<Double>> valuePairs, HashSet<String> set, double value) {
+            if (set.contains(start)) {
+                return 0.0;
+            }
+            if (!pairs.containsKey(start)) {
+                return 0.0;
+            }
+            if (start.equals(end)) {
+                return value;
+            }
+            set.add(start);
 
-        List<String> stringList = pairs.get(start);
-        List<Double> valueList = valuePairs.get(start);
-        double tmp = 0.0;
-        for (int i = 0; i < stringList.size(); i++) {
-            tmp = dfs(stringList.get(i), end, pairs, valuePairs, set, value * valueList.get(i));
-            if (tmp != 0.0) {
-                break;
+            List<String> stringList = pairs.get(start);
+            List<Double> valueList = valuePairs.get(start);
+            double tmp = 0.0;
+            for (int i = 0; i < stringList.size(); i++) {
+                tmp = dfs(stringList.get(i), end, pairs, valuePairs, set, value * valueList.get(i));
+                if (tmp != 0.0) {
+                    break;
+                }
             }
+            set.remove(start);
+            return tmp;
         }
-        set.remove(start);
-        return tmp;
     }
-
 }