add

5.leetcode/src/com/fanxb/common/Q1711.java

@@ -0,0 +1,38 @@
+package com.fanxb.common;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * 两数相加
+ *
+ * @author fanxb
+ * @date 2021/6/1
+ **/
+public class Q1711 {
+
+    public int countPairs(int[] deliciousness) {
+        int maxValue = 0;
+        for (int item : deliciousness) {
+            if (item > maxValue) {
+                maxValue = item;
+            }
+        }
+        Map<Integer, Integer> numCountMap = new HashMap<>(deliciousness.length);
+        double val = Math.pow(10, 9) + 7;
+        long count = 0;
+        for (int num : deliciousness) {
+            for (int a = 1; a <= maxValue*2; a <<= 1) {
+                count += numCountMap.getOrDefault(a - num, 0);
+            }
+            numCountMap.put(num, numCountMap.getOrDefault(num, 0) + 1);
+        }
+        return (int) (count % val);
+    }
+
+    public static void main(String[] args) {
+        System.out.println(new Q1711().countPairs(new int[]{1, 3, 5, 7, 9}));
+    }
+}