feat: add solutions to lc problem: No. 1711.Count Good Meals

Author: maolonglong

solution/1700-1799/1711.Count Good Meals/README.md

@@ -44,6 +44,8 @@
 
 ## 解法
 
+用最暴力的方法枚举每对元素肯定会超时，可以用哈希表优化对**之前元素出现次数**的查询。
+
 <!-- 这里可写通用的实现逻辑 -->
 
 <!-- tabs:start -->
@@ -53,15 +55,74 @@
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```python
-
+class Solution:
+    def countPairs(self, deliciousness: List[int]) -> int:
+        mod = 1000000007
+        limit = max(deliciousness) * 2
+        pairs = 0
+        freq = collections.defaultdict(int)
+        for d in deliciousness:
+            target = 1
+            while target <= limit:
+                pairs = (pairs + freq[target - d]) % mod
+                target = target << 1
+            freq[d] += 1
+        return pairs
 ```
 
 ### **Java**
 
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```java
+class Solution {
+
+    private static final int MOD = 1000000007;
+
+    public int countPairs(int[] deliciousness) {
+        int limit = Arrays.stream(deliciousness).max().getAsInt() * 2;
+        int pairs = 0;
+        Map<Integer, Integer> freq = new HashMap<>();
+        for (int d : deliciousness) {
+            for (int sum = 1; sum <= limit; sum <<= 1) {
+                int count = freq.getOrDefault(sum - d, 0);
+                pairs = (pairs + count) % MOD;
+            }
+            freq.merge(d, 1, Integer::sum);
+        }
+        return pairs;
+    }
+}
+```
 
+### **Go**
+
+```go
+const mod int = 1e9 + 7
+
+func countPairs(deliciousness []int) int {
+	limit := 0
+	for _, d := range deliciousness {
+		limit = max(limit, d)
+	}
+	limit *= 2
+	pairs := 0
+	freq := make(map[int]int)
+	for _, d := range deliciousness {
+		for sum := 1; sum <= limit; sum <<= 1 {
+			pairs = (pairs + freq[sum-d]) % mod
+		}
+		freq[d]++
+	}
+	return pairs
+}
+
+func max(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}
 ```
 
 ### **...**

solution/1700-1799/1711.Count Good Meals/README_EN.md

@@ -45,13 +45,72 @@ Their respective sums are 4, 8, 8, and 16, all of which are powers of 2.
 ### **Python3**
 
 ```python
-
+class Solution:
+    def countPairs(self, deliciousness: List[int]) -> int:
+        mod = 1000000007
+        limit = max(deliciousness) * 2
+        pairs = 0
+        freq = collections.defaultdict(int)
+        for d in deliciousness:
+            target = 1
+            while target <= limit:
+                pairs = (pairs + freq[target - d]) % mod
+                target = target << 1
+            freq[d] += 1
+        return pairs
 ```
 
 ### **Java**
 
 ```java
+class Solution {
+
+    private static final int MOD = 1000000007;
+
+    public int countPairs(int[] deliciousness) {
+        int limit = Arrays.stream(deliciousness).max().getAsInt() * 2;
+        int pairs = 0;
+        Map<Integer, Integer> freq = new HashMap<>();
+        for (int d : deliciousness) {
+            for (int sum = 1; sum <= limit; sum <<= 1) {
+                int count = freq.getOrDefault(sum - d, 0);
+                pairs = (pairs + count) % MOD;
+            }
+            freq.merge(d, 1, Integer::sum);
+        }
+        return pairs;
+    }
+}
+```
 
+### **Go**
+
+```go
+const mod int = 1e9 + 7
+
+func countPairs(deliciousness []int) int {
+	limit := 0
+	for _, d := range deliciousness {
+		limit = max(limit, d)
+	}
+	limit *= 2
+	pairs := 0
+	freq := make(map[int]int)
+	for _, d := range deliciousness {
+		for sum := 1; sum <= limit; sum <<= 1 {
+			pairs = (pairs + freq[sum-d]) % mod
+		}
+		freq[d]++
+	}
+	return pairs
+}
+
+func max(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}
 ```
 
 ### **...**

solution/1700-1799/1711.Count Good Meals/Solution.go

@@ -0,0 +1,25 @@
+const mod int = 1e9 + 7
+
+func countPairs(deliciousness []int) int {
+	limit := 0
+	for _, d := range deliciousness {
+		limit = max(limit, d)
+	}
+	limit *= 2
+	pairs := 0
+	freq := make(map[int]int)
+	for _, d := range deliciousness {
+		for sum := 1; sum <= limit; sum <<= 1 {
+			pairs = (pairs + freq[sum-d]) % mod
+		}
+		freq[d]++
+	}
+	return pairs
+}
+
+func max(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}

solution/1700-1799/1711.Count Good Meals/Solution.java

@@ -0,0 +1,18 @@
+class Solution {
+
+    private static final int MOD = 1000000007;
+
+    public int countPairs(int[] deliciousness) {
+        int limit = Arrays.stream(deliciousness).max().getAsInt() * 2;
+        int pairs = 0;
+        Map<Integer, Integer> freq = new HashMap<>();
+        for (int d : deliciousness) {
+            for (int sum = 1; sum <= limit; sum <<= 1) {
+                int count = freq.getOrDefault(sum - d, 0);
+                pairs = (pairs + count) % MOD;
+            }
+            freq.merge(d, 1, Integer::sum);
+        }
+        return pairs;
+    }
+}

solution/1700-1799/1711.Count Good Meals/Solution.py

@@ -0,0 +1,13 @@
+class Solution:
+    def countPairs(self, deliciousness: List[int]) -> int:
+        mod = 1000000007
+        limit = max(deliciousness) * 2
+        pairs = 0
+        freq = collections.defaultdict(int)
+        for d in deliciousness:
+            target = 1
+            while target <= limit:
+                pairs = (pairs + freq[target - d]) % mod
+                target = target << 1
+            freq[d] += 1
+        return pairs