DP

 fibaonaci series using dp

class Solution {

public int usingDp(int n, int dp[])

{

if(n <= 1)

return n ;

if(dp[n] != -1)

return dp[n];

return dp[n]=usingDp(n-1,dp) + usingDp(n-2,dp);

}

public int fib(int n) {

int [] dp ={n+1,-1};

int no = usingDp(n, dp);

return no;

}

}

TC = o(n) linear

SC = o(n)+o(n) {array, stack space for recur}