平胸而论 线段树写错可太难调试了

#include <bits/stdc++.h>
using namespace std;
const int N = 2e5+10;
int n,p,tot;
int t[N << 4];
void update(int x,int L = 1,int R = n,int rt = 1)
{
    if(L == R)
    {
        t[rt] = x;
        return;
    }
    int mid = L + R >> 1;
    if(tot <= mid) update(x,L,mid,rt << 1);
    else update(x,mid+1,R,rt<<1|1);
    t[rt] = max(t[rt], max(t[rt << 1], t[rt << 1 | 1]));
    //printf("%d %d %d %d\n",rt,t[rt],L,R);
}
int query(int l,int r,int L = 1,int R = n,int rt = 1)
{
    if(l > r) return 0;
    //printf("%d %d %d %d %d\n",l,r,L,R,r);
    if(l <= L && R <= r) return t[rt];
    int mid = L + R >> 1;
    if(r <= mid) return query(l,r,L,mid,rt<<1);
    else if(l > mid) return query(l,r,mid+1,R,rt<<1|1);
    else return max(query(l,mid,L,mid,rt<<1),query(mid+1,r,mid+1,R,rt<<1|1));
}
int main()
{
    cin >> n >> p;
    char op[2];
    int pre=0;
    for(int i = 1,x; i <= n; ++i)
    {
        scanf("%s%d",op,&x);
        if(op[0]=='A')
        {
            tot++;
            update((x+pre)%p);
        }
        else
        {
            int l = tot - x + 1, r = tot;
            pre = query(l,r);
            printf("%d\n",pre);
        }
    }

}