Create 920.Number-of-Music-Playlists.cpp

Author: wisdompeak

Dynamic_Programming/920.Number-of-Music-Playlists/920.Number-of-Music-Playlists.cpp

@@ -0,0 +1,20 @@
+class Solution {
+public:
+ int numMusicPlaylists(int N, int L, int K) 
+ {
+ auto dp = vector<vector<long>>(L+1,vector<long>(N+1,0));
+ dp[1][1] = N;
+ long MOD = 1e9+7;
+ 
+ for (int i=2; i<=L; i++)
+ for (int j=1; j<=min(N,i); j++)
+ {
+ if (j>K) dp[i][j] += dp[i-1][j]*(j-K);
+ dp[i][j]%=MOD;
+ if (N>j-1) dp[i][j] += dp[i-1][j-1]*(N-j+1);
+ dp[i][j]%=MOD; 
+ }
+ 
+ return dp[L][N];
+ }
+};