hash表

const int MAXM=1e7+7;
struct{
    int next[MAXM],head[MAXM],ans[MAXM],size;
    ll state[MAXM];
 
    void init(){
        size=0;
        memset(head,0,sizeof(head));
    }
 
    ll check(ll val){
        int h=(val%MAXM+MAXM)%MAXM;
        for(int i=head[h];i;i=next[i]){
            if(state[i]==val)return ans[i];
        }
        return 0;
    }
 
    ll insert(ll val,ll ans2){
        int h=(val%MAXM+MAXM)%MAXM;
        for(int i=head[h];i;i=next[i]){
            if(state[i]==val)return 1;
        }
        state[size]=val;
        next[size]=head[h];
        ans[size]=ans2;
        head[h]=size++;
        return 0;
    }
    void del(ll val)
    {
        int h=(val%MAXM+MAXM)%MAXM; head[h]=0;
    }
}H;