Solutions

Author: trinhminhtriet

solutions/1700-1799/1780.check-if-number-is-a-sum-of-powers-of-three/Solution.cs

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+public class Solution {
+    public bool CheckPowersOfThree(int n) {
+        while (n > 0) {
+            if (n % 3 > 1) {
+                return false;
+            }
+            n /= 3;
+        }
+        return true;
+    }
+}

solutions/1700-1799/1780.check-if-number-is-a-sum-of-powers-of-three/Solution.rs

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+impl Solution {
+    pub fn check_powers_of_three(n: i32) -> bool {
+        let mut n = n;
+        while n > 0 {
+            if n % 3 > 1 {
+                return false;
+            }
+            n /= 3;
+        }
+        true
+    }
+}

solutions/1700-1799/1781.sum-of-beauty-of-all-substrings/Solution.rs

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+impl Solution {
+    pub fn beauty_sum(s: String) -> i32 {
+        let mut ans = 0;
+        let n = s.len();
+        let s: Vec<char> = s.chars().collect();
+
+        for i in 0..n {
+            let mut cnt = vec![0; 26];
+            for j in i..n {
+                cnt[s[j] as usize - 'a' as usize] += 1;
+                let mut mi = 1000;
+                let mut mx = 0;
+                for &v in &cnt {
+                    if v > 0 {
+                        mi = mi.min(v);
+                        mx = mx.max(v);
+                    }
+                }
+                ans += mx - mi;
+            }
+        }
+        ans
+    }
+}

solutions/1700-1799/1781.sum-of-beauty-of-all-substrings/Solution.ts

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+function beautySum(s: string): number {
+    let ans = 0;
+    for (let i = 0; i < s.length; ++i) {
+        const cnt = new Map();
+        for (let j = i; j < s.length; ++j) {
+            cnt.set(s[j], (cnt.get(s[j]) || 0) + 1);
+            const t = Array.from(cnt.values());
+            ans += Math.max(...t) - Math.min(...t);
+        }
+    }
+    return ans;
+}