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| #include <bits/stdc++.h>
using namespace std;
const int N = 5e6 + 5, inf = 1e9;
int n, m, a[N], id[N];
int buc[N], tp;
int rt, tot;
int newnode() { return (tp ? buc[tp--] : ++tot); }
int ch[N][2], sz[N], val[N], sum[N], mx[N], lx[N], rx[N], fa[N];
bool same[N], rev[N];
bool rs(int x) { return ch[fa[x]][1]==x; }
void up(int p)
{
if(!p) return;
int l = ch[p][0], r = ch[p][1];
sum[p] = sum[l] + sum[r] + val[p];
sz[p] = sz[l] + sz[r] + 1;
mx[p] = max({mx[l], mx[r], rx[l]+lx[r]+val[p]});
lx[p] = max(lx[l], sum[l]+val[p]+lx[r]);
rx[p] = max(rx[r], sum[r]+val[p]+rx[l]);
}
void setv(int p, int v)
{
if(!p) return;
val[p] = v, sum[p] = v*sz[p];
lx[p] = rx[p] = (sum[p]>0 ? sum[p] : 0);
mx[p] = (sum[p]>0 ? sum[p] : val[p]);
}
void setrev(int p)
{
if(!p) return;
swap(ch[p][0], ch[p][1]);
swap(lx[p], rx[p]);
}
void down(int p)
{
int l = ch[p][0], r = ch[p][1];
if(same[p])
{
same[l] = 1, setv(l, val[p]);
same[r] = 1, setv(r, val[p]);
same[p] = 0;
}
if(rev[p])
{
rev[l] ^= 1, setrev(l);
rev[r] ^= 1, setrev(r);
rev[p] = 0;
}
}
void rotate(int x)
{
int y = fa[x], z = fa[y], k = rs(x), w = ch[x][k^1];
ch[y][k] = w; fa[w] = y;
ch[z][rs(y)] = x; fa[x] = z;
ch[x][k^1] = y; fa[y] = x;
up(y); up(x);
}
void splay(int x, int g=0)
{
while(fa[x]!=g)
{
int y = fa[x], z = fa[y];
if(z!=g) (rs(x)==rs(y) ? rotate(y) : rotate(x));
rotate(x);
}
if(!g) rt = x;
}
int kth(int p, int k)
{
down(p);
if(ch[p][0]&&sz[ch[p][0]]>=k) return kth(ch[p][0], k);
else if(sz[ch[p][0]]+1==k) return p;
else return kth(ch[p][1], k-sz[ch[p][0]]-1);
}
int split(int l, int r)
{
int x = kth(rt, l-1), y = kth(rt, r+1);
splay(x); splay(y, x);
return ch[y][0];
}
void makesame(int l, int r, int v)
{
int x = split(l, r), y = fa[x];
setv(x, v), same[x] = 1;
up(y); up(fa[y]);
}
void reverse(int l, int r)
{
int x = split(l, r), y = fa[x];
setrev(x), rev[x] ^= 1;
up(y); up(fa[y]);
}
void rec(int x)
{
if(!x) return;
int l = ch[x][0], r = ch[x][1];
rec(l); rec(r);
buc[++tp] = x;
fa[x] = ch[x][0] = ch[x][1] = 0, rev[x] = same[x] = 0;
sz[x] = val[x] = sum[x] = mx[x] = lx[x] = rx[x] = 0;
}
void del(int l, int r)
{
int x = split(l, r), y = fa[x];
rec(ch[y][0]); ch[y][0] = 0;
up(y); up(fa[y]);
}
void bld(int l, int r, int f)
{
if(l>r) return;
int mid = (l+r)>>1, p = id[mid];
val[p] = a[mid];
if(f) fa[p] = id[f], ch[id[f]][mid>f] = p;
if(l==r)
{
mx[p] = sum[p] = a[l];
same[p] = rev[p] = 0;
lx[p] = rx[p] = max(a[l], 0);
sz[p] = 1;
ch[p][0] = ch[p][1] = 0;
}
bld(l, mid-1, mid);
bld(mid+1, r, mid);
up(p);
}
void ins(int l, int r)
{
for(int i=1; i<=r-l+1; i++)
{
scanf("%d", &a[i]);
id[i] = newnode();
}
bld(1, r-l+1, 0);
int x = kth(rt, l), y = kth(rt, l+1);
splay(x); splay(y, x);
int z = id[(r-l+2)>>1];
fa[z] = y, ch[y][0] = z;
up(y); up(x);
}
int main()
{
scanf("%d%d", &n, &m);
mx[0] = -inf, a[1] = -inf, a[n+2] = inf;
for(int i=1; i<=n; i++) scanf("%d", &a[i+1]);
for(int i=1; i<=n+2; i++) id[i] = newnode();
bld(1, n+2, 0);
rt = (n+3)>>1;
while(m--)
{
static char com[10];
scanf("%s", com);
int l, r;
if(com[0]!='M'||com[2]!='X') scanf("%d%d", &l, &r);
++l, r = l + r - 1;
if(com[0]=='I') ins(l, r);
if(com[0]=='D') del(l, r);
if(com[0]=='M')
{
if(com[2]=='X') printf("%d\n", mx[split(2, sz[rt]-1)]);
else
{
int v; scanf("%d", &v);
makesame(l, r, v);
}
}
if(com[0]=='R') reverse(l, r);
if(com[0]=='G') printf("%d\n", sum[split(l, r)]);
}
return 0;
}
|