def?forward_viterbi（obs?states?start_p?trans_p?emit_p）:
????T?=?{}
????for?state?in?states:
????????##??????????prob.???????????V.?path??V.?prob.
????????T[state]?=?（start_p[state]?[state]?start_p[state]）
????for?output?in?obs:
????????print?T
????????U?=?{}
????????for?next_state?in?states:
????????????total?=?0
????????????argmax?=?None
????????????valmax?=?0
????????????for?source_state?in?states:
????????????????（prob?v_path?v_prob）?=?T[source_state]
????????????????p?=?emit_p[source_state][output]?*?trans_p[source_state][next_state]
????????????????#caculate
????????????????prob?*=?p
????????????????v_prob?*=?p
????????????????#the?different?way?to?gain
????????????????total?+=?prob
????????????????if?v_prob?>?valmax:
????????????????????argmax?=?v_path?+?[next_state]
????????????????????valmax?=?v_prob
????????????U[next_state]?=?（total?argmax?valmax）
????????T?=?U
????#print?T
????##?apply?sum/max?to?the?final?states:
????total?=?0
????argmax?=?None
????v