Untitled

class Solution:
    def mincostTickets(self, days: List[int], costs: List[int]) -> int:
 
        def rec(i,d):
            if i>=len(days):
                return 0
            if d>days[len(days)-1]:
                return 0
            while(i<len(days) and days[i]<=d):
                i+=1

            if (i,d) not in dp:
                
                
                a=costs[0]+rec(i+1,d+1)
                
                
                b=costs[1]+rec(i+1,d+7)
                
                c=costs[2]+rec(i+1,d+30)
                dp[(i,d)]= min(min(a,b),c)
            return dp[(i,d)]
        dp={}
        
        return rec(0,0)