please tell why the last 3 test cases are giving runtime error on the soln .I used the approach suggested in the video in the bottom up manner.
Test cases not getting passed completely
Hey @rohangupta569
Create Dp arrays dynamically 
int **dp=new int*[str1.size()+1];
for(int i=0;i<=str1.length();i++){
dp[i]= new int[str2.size()+1];
}
Thanx,Now its getting passed but why did static allocation caused a problem here?
Because max static allocated array u can create in function is close to 10^6
And ur array could be of 4*10^6 because str length<=2000