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#include <fstream>
#include <algorithm>
using namespace std;
class InParser {
private:
FILE *fin;
char *buff;
int sp;
char read_ch() {
++sp;
if (sp == 4096) {
sp = 0;
fread(buff, 1, 4096, fin);
}
return buff[sp];
}
public:
InParser(const char* nume) {
fin = fopen(nume, "r");
buff = new char[4096]();
sp = 4095;
}
InParser& operator >> (int &n) {
char c;
while (!isdigit(c = read_ch()) && c != '-');
int sgn = 1;
if (c == '-') {
n = 0;
sgn = -1;
} else {
n = c - '0';
}
while (isdigit(c = read_ch())) {
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
InParser& operator >> (long long &n) {
char c;
n = 0;
while (!isdigit(c = read_ch()) && c != '-');
long long sgn = 1;
if (c == '-') {
n = 0;
sgn = -1;
} else {
n = c - '0';
}
while (isdigit(c = read_ch())) {
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
};
class OutParser {
private:
FILE *fout;
char *buff;
int sp;
void write_ch(char ch) {
if (sp == 50000) {
fwrite(buff, 1, 50000, fout);
sp = 0;
buff[sp++] = ch;
} else {
buff[sp++] = ch;
}
}
public:
OutParser(const char* name) {
fout = fopen(name, "w");
buff = new char[50000]();
sp = 0;
}
~OutParser() {
fwrite(buff, 1, sp, fout);
fclose(fout);
}
OutParser& operator << (int vu32) {
if (vu32 <= 9) {
write_ch(vu32 + '0');
} else {
(*this) << (vu32 / 10);
write_ch(vu32 % 10 + '0');
}
return *this;
}
OutParser& operator << (long long vu64) {
if (vu64 <= 9) {
write_ch(vu64 + '0');
} else {
(*this) << (vu64 / 10);
write_ch(vu64 % 10 + '0');
}
return *this;
}
OutParser& operator << (char ch) {
write_ch(ch);
return *this;
}
OutParser& operator << (const char *ch) {
while (*ch) {
write_ch(*ch);
++ch;
}
return *this;
}
};
struct aww
{
long long st, dr, mij;
int lst, ldr, lg;
aww ()
{
st = dr = mij = -20000000000000000LL;
lst = ldr = lg = 0;
}
aww (long long x)
{
st = dr = mij = x;
lst = ldr = lg = 1;
}
} arb[200010];
int n, m;
inline aww unite (aww a, aww b)
{
aww sol;
sol.mij = a.dr + b.st;
if (a.ldr == a.lg) sol.st = sol.mij, sol.lst = a.lg + b.lst;
if (b.lst == b.lg) sol.dr = sol.mij, sol.ldr = b.lg + a.ldr;
aww rez;
rez.lg = a.lg + b.lg;
rez.lst = a.lst;
rez.st = a.st;
if (a.lst == a.lg)
if (rez.st < rez.st + b.st)
rez.st += b.st,
rez.lst += b.lst;
rez.ldr = b.ldr;
rez.dr = b.dr;
if (b.ldr == b.lg)
if (rez.dr < rez.dr + a.dr)
rez.dr += a.dr,
rez.ldr += a.ldr;
if (sol.st > rez.st) rez.st = sol.st, rez.lst = sol.lst;
if (sol.dr > rez.dr) rez.dr = sol.dr, rez.ldr = sol.ldr;
rez.mij = max (max (a.mij, b.mij), sol.mij);
rez.mij = max (max (rez.st, rez.dr), rez.mij);
return rez;
}
inline void build ()
{
for (int i = n - 1; i; --i)
arb[i] = unite (arb[i << 1], arb[i << 1 | 1]);
}
inline long long querry (int st, int dr)
{
aww rst, rdr;
for (st += n - 1, dr += n; st < dr; st >>= 1, dr >>= 1)
{
if (st & 1) rst = unite (rst, arb[st++]);
if (dr & 1) rdr = unite (arb[--dr], rdr);
}
return unite (rst, rdr).mij;
}
int main ()
{
InParser cin ("sequencequery.in");
OutParser cout ("sequencequery.out");
cin >> n >> m;
for (int i = 0; i < n; ++i)
{
long long x;
cin >> x;
arb[i + n] = aww (x);
}
build ();
for (; m; --m)
{
int x, y;
cin >> x >> y;
long long rez = querry (x, y);
if (rez < 0)
{
cout << '-';
rez = -rez;
}
cout << rez << '\n';
}
return 0;
}