Create number-of-people-aware-of-a-secret.py

Author: kamyu104

Python/number-of-people-aware-of-a-secret.py

@@ -0,0 +1,18 @@
+# Time:  O(n)
+# Space: O(f)
+
+# dp
+class Solution(object):
+    def peopleAwareOfSecret(self, n, delay, forget):
+        """
+        :type n: int
+        :type delay: int
+        :type forget: int
+        :rtype: int
+        """
+        MOD = 10**9+7
+        dp = [0]*forget
+        dp[0] = 1
+        for i in xrange(1, n):
+            dp[i%forget] = ((dp[(i-1)%forget] if i-1 else 0)-dp[i%forget]+dp[(i-delay)%forget]) % MOD
+        return sum(dp)%MOD