Runtime: 2371 ms (Top 59.7%) | Memory: 646.15 MB (Top 20.7%)

Author: AnasImloul

scripts/algorithms/W/Ways to Express an Integer as Sum of Powers/Ways to Express an Integer as Sum of Powers.py

@@ -0,0 +1,27 @@
+# Runtime: 2371 ms (Top 59.7%) | Memory: 646.15 MB (Top 20.7%)
+
+class Solution:
+    MOD = 1_000_000_007
+
+    def numberOfWays(self, num: int, power: int) -> int:
+        @cache
+        def calc_ways(i: int, left: int) -> int:
+            if left == 0:
+                return 1
+            elif left < 0 or i >= len(candidates) or candidates[i] > left:
+                return 0
+            else:
+                return (
+                    calc_ways(i + 1, left) + calc_ways(i + 1, left - candidates[i])
+                ) % self.MOD
+
+        candidates = list(self.__get_candidates(num, power))
+        return calc_ways(0, num)
+
+    @staticmethod
+    def __get_candidates(n: int, p: int) -> Generator:
+        for num in map(lambda x: x ** p, range(1, n + 1)):
+            if num <= n:
+                yield num
+            else:
+                break