match parentheses from one end of s and ret pointer i

if f can be formed in the form of p->q: return (p,q), else return f,None p,q,f are all formula s

int CompareTimes(int key0){ int cnt = 1; Node<Elem>* p; p = hash[key0]->head->next; while(p && key0 != p->data.number){ p = p->next; cnt++; } return c

this is used to visit every instruction in function if any instruction can be eliminated, do something(check all it's operands) else just do nothing

recursion version

O(n^2)

i think this is the main dce function, it calls the core function DCEInstruction it's a iteration structure

visit s from i until s[i] isn't NON, then return the num of continuous NON and the pointer i

the main algorithm, calling other stuff