这种题目完全不会debug…
对着y总代码调通后突然有种进入贤者模式的感觉…

#include<iostream>
#include<cstring>

using namespace std;
const int N = 500010, INF = 0x3f3f3f3f;
int n, m;
struct Node{
    int s[2], p;
    int ts, ls, rs, ms;
    int rev, same;
    int v, size;
    void init(int v_, int p_)
    {
        s[0] = s[1] = 0;
        v = v_, p = p_;
        rev = same = 0;
        ts = ms = v, size = 1;
        ls = rs = max(0, v);
    }
} tr[N];
int root, nodes[N], tt(0);
int a[N];

void pushup(int x)
{
    auto &root = tr[x], &l = tr[tr[x].s[0]], &r = tr[tr[x].s[1]];
    root.size = l.size + r.size + 1;
    root.ts = l.ts + r.ts + root.v;
    root.ls = max(l.ls, l.ts + root.v + r.ls);
    root.rs = max(r.rs, r.ts + root.v + l.rs);
    root.ms = max(r.ms, max(l.ms, r.ls + l.rs + root.v));
}

void pushdown(int x)
{
    auto &root = tr[x], &l = tr[tr[x].s[0]], &r = tr[tr[x].s[1]];
    if(root.same)
    {
        root.same = root.rev = 0;
        if(root.s[0]) l.v = root.v, l.same = 1, l.ts = l.size * l.v;
        if(root.s[1]) r.v = root.v, r.same = 1, r.ts = r.size * r.v;
        if(root.v > 0)
        {
            if(root.s[0]) l.ms = l.rs = l.ls = l.ts;
            if(root.s[1]) r.ms = r.rs = r.ls = r.ts;
        }
        else
        {
            if(root.s[0]) l.ms = l.v, l.ls = l.rs = 0;
            if(root.s[1]) r.ms = r.v, r.ls = r.rs = 0;
        }
    }
    else if(root.rev)
    {
        root.rev = 0, l.rev ^= 1, r.rev ^= 1;
        if(root.s[0]) swap(l.rs, l.ls), swap(l.s[0], l.s[1]);
        if(root.s[1]) swap(r.ls, r.rs), swap(r.s[0], r.s[1]);
    }
}


void rotate(int x)
{
    int y = tr[x].p, z = tr[y].p;
    int k = tr[y].s[1] == x;
    tr[z].s[tr[z].s[1] == y] = x, tr[x].p = z;
    tr[y].s[k] = tr[x].s[k ^ 1], tr[tr[x].s[k ^ 1]].p = y;
    tr[x].s[k ^ 1] = y, tr[y].p = x;
    pushup(y), pushup(x);
}

void splay(int x, int k)
{
    while(tr[x].p != k)
    {
        int y = tr[x].p, z = tr[y].p;
        if(z != k)
            if((tr[z].s[1] == y) ^ (tr[y].s[1] == x)) rotate(x);
            else rotate(y);
        rotate(x);
    }
    if(!k) root = x;
}

int get_k(int k)
{
    int u = root;
    while(true)
    {
        pushdown(u);
        if(tr[tr[u].s[0]].size >= k) u = tr[u].s[0];
        else if(tr[tr[u].s[0]].size + 1 == k) return u;
        else k -= tr[tr[u].s[0]].size + 1, u = tr[u].s[1];
    }
    return -1;
}

void del(int u)
{
    if(tr[u].s[0]) del(tr[u].s[0]);
    if(tr[u].s[1]) del(tr[u].s[1]);
    nodes[++tt] = u;
}

int build(int l, int r, int p)
{
    int mid = l + r >> 1;
    int u = nodes[tt--];
    tr[u].init(a[mid], p);
    if(l < mid) tr[u].s[0] = build(l, mid - 1, u);
    if(r > mid) tr[u].s[1] = build(mid + 1, r, u);
    pushup(u);
    return u;
}


int main()
{
    scanf("%d%d", &n, &m);
    for(int i = 1; i < N; ++i) nodes[++tt] = i;
    tr[0].ms = a[0] = a[n + 1] = -INF;
    for(int i = 1; i <= n; ++i) scanf("%d", a + i);
    root = build(0, n + 1, 0);

    char op[20];
    while(m --)
    {
        scanf("%s", op);
        if(!strcmp(op, "INSERT"))
        {
            int pos, cnt;
            scanf("%d%d", &pos, &cnt);
            for(int i = 1; i <= cnt; ++i) scanf("%d", a + i);
            int l = get_k(pos + 1), r = get_k(pos + 2);
            splay(l, 0), splay(r, l);
            int u = build(1, cnt, r);
            tr[r].s[0] = u;
            pushup(r), pushup(l);
        }
        else if(!strcmp(op, "DELETE"))
        {
            int pos, cnt;
            scanf("%d%d", &pos, &cnt);
            int l = get_k(pos), r = get_k(pos + cnt + 1);
            splay(l, 0), splay(r, l);
            del(tr[r].s[0]);
            tr[r].s[0] = 0;
            pushup(r), pushup(l);
        }
        else if(!strcmp(op, "MAKE-SAME"))
        {
            int pos, cnt, c;
            scanf("%d%d%d", &pos, &cnt, &c);
            int l = get_k(pos), r = get_k(pos + cnt + 1);
            splay(l, 0), splay(r, l);
            auto &son = tr[tr[r].s[0]];
            son.same = 1, son.rev = 0, son.v = c, son.ts = c * son.size;
            if(c > 0) son.ms = son.ls = son.rs = son.ts;
            else son.ms = c, son.ls = son.rs = 0;
            pushup(r), pushup(l);
        }
        else if(!strcmp(op, "REVERSE"))
        {
            int pos, cnt;
            scanf("%d%d", &pos, &cnt);
            int l = get_k(pos), r = get_k(pos + cnt + 1);
            splay(l, 0), splay(r, l);
            auto& son = tr[tr[r].s[0]];
            son.rev ^= 1;
            swap(son.rs, son.ls);
            swap(son.s[0], son.s[1]);
            pushup(r), pushup(l);
        }
        else if(!strcmp(op, "GET-SUM"))
        {
            int pos, cnt;
            scanf("%d%d", &pos, &cnt);
            int l = get_k(pos), r = get_k(pos + cnt + 1);
            splay(l, 0), splay(r, l);
            printf("%d\n", tr[tr[r].s[0]].ts);
        }
        else printf("%d\n", tr[root].ms);
    }
    return 0;
}