give string s t return number distinct subsequence s equal tThe test case generate answer fit 32bit sign integer Example 1input s rabbbit t rabbitoutput 3explanationas show 3 way generate rabbit srabbbitrabbbitrabbbitExample 2input s babgbag t bagoutput 5explanationas show 5 way generate bag sbabgbagbabgbagbabgbagbabgbagbabgbag Constraints1 slength tlength 1000 t consist english letter