feat: 完全背包问题

完全背包问题

Change-Id: I9ea91200ba29e448ed7575ff1636898751a164d9

Author: 骏钰 王

main/com/ect/bag/CompleteBag.java

@@ -0,0 +1,42 @@
+package com.ect.bag;
+
+/**
+ * 完全背包问题
+ * 完全背包是每个物品都无限
+ *
+ * F[i,v] = max{F[i − 1,v],F[i,v − Ci] + Wi}
+ *
+ * 如果用一维数组来表示的话，F［v］在左值时表示的是这一阶段的，要保证右面的F［v］是上一阶段的，而F［v－ci］是这一阶段的，所以～顺序计算！！
+ *
+ * Created by Mr Wang :) on 18-1-30.
+ */
+public class CompleteBag {
+
+
+    public void compelete(int[][] nums, int[] weights, int[] values, int capacity) {
+
+        for (int i = 0; i < weights.length; i++) {
+
+            for (int j = weights[i]; j < capacity; j++) {
+                for (int k = 0; k * weights[i] < j; k++) {
+                    nums[i][j] = Math.max(nums[i - 1][j], nums[i - 1][j - k * weights[i]] + k * values[i]);
+                }
+            }
+        }
+
+    }
+
+    // 完全背包是顺序
+    void bagBak(int[] nums, int[] weight, int[] values, int capacity) {
+
+        for (int i = 1; i <= weight.length; i++) {
+
+            // 顺序，背包容量逐渐变大，能放下物品i就放
+            for (int j = weight[i]; j <= capacity; j++) {
+                nums[j] = Math.max(nums[j], nums[j - weight[i]] + values[i]);
+            }
+        }
+    }
+
+
+}