Problem p02599 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <algorithm>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <iostream>
#include <map>
#include <set>
#include <string>
#include <vector>

/** Interface */

template <class T = int> inline T readInt();
inline double readDouble();
inline int readUInt();
inline int readChar();
inline void readWord(char *s);
inline bool readLine(char *s); // do not save '\\n'
inline bool isEof();
inline int peekChar();
inline bool seekEof();

template <class T> inline void writeInt(T x, int len = -1);
template <class T> inline void writeUInt(T x, int len = -1);
inline void writeChar(int x);
inline void writeWord(const char *s);
inline void writeDouble(double x, int len = 0);
inline void flush();

/** Read */

static const int buf_size = 4096;

static char buf[buf_size];
static int buf_len = 0, buf_pos = 0;

inline bool isEof() {
  if (buf_pos == buf_len) {
    buf_pos = 0, buf_len = fread(buf, 1, buf_size, stdin);
    if (buf_pos == buf_len)
      return 1;
  }
  return 0;
}

inline int getChar() { return isEof() ? -1 : buf[buf_pos++]; }

inline int peekChar() { return isEof() ? -1 : buf[buf_pos]; }

inline bool seekEof() {
  int c;
  while ((c = peekChar()) != -1 && c <= 32)
    buf_pos++;
  return c == -1;
}

inline int readChar() {
  int c = getChar();
  while (c != -1 && c <= 32)
    c = getChar();
  return c;
}

inline int readUInt() {
  int c = readChar(), x = 0;
  while ('0' <= c && c <= '9')
    x = x * 10 + c - '0', c = getChar();
  return x;
}

template <class T> inline T readInt() {
  int s = 1, c = readChar();
  T x = 0;
  if (c == '-')
    s = -1, c = getChar();
  while ('0' <= c && c <= '9')
    x = x * 10 + c - '0', c = getChar();
  return s == 1 ? x : -x;
}

inline double readDouble() {
  int s = 1, c = readChar();
  double x = 0;
  if (c == '-')
    s = -1, c = getChar();
  while ('0' <= c && c <= '9')
    x = x * 10 + c - '0', c = getChar();
  if (c == '.') {
    c = getChar();
    double coef = 1;
    while ('0' <= c && c <= '9')
      x += (c - '0') * (coef *= 1e-1), c = getChar();
  }
  return s == 1 ? x : -x;
}

inline void readWord(char *s) {
  int c = readChar();
  while (c > 32)
    *s++ = c, c = getChar();
  *s = 0;
}

inline bool readLine(char *s) {
  int c = getChar();
  while (c != '\\n' && c != -1)
    *s++ = c, c = getChar();
  *s = 0;
  return c != -1;
}

/** Write */

static int write_buf_pos = 0;
static char write_buf[buf_size];

inline void writeChar(int x) {
  if (write_buf_pos == buf_size)
    fwrite(write_buf, 1, buf_size, stdout), write_buf_pos = 0;
  write_buf[write_buf_pos++] = x;
}

inline void flush() {
  if (write_buf_pos)
    fwrite(write_buf, 1, write_buf_pos, stdout), write_buf_pos = 0;
}

template <class T> inline void writeInt(T x, int output_len) {
  if (x < 0)
    writeChar('-'), x = -x;

  char s[24];
  int n = 0;
  while (x || !n)
    s[n++] = '0' + x % 10, x /= 10;
  while (n < output_len)
    s[n++] = '0';
  while (n--)
    writeChar(s[n]);
}

template <class T> inline void writeUInt(T x, int output_len) {
  char s[24];
  int n = 0;
  while (x || !n)
    s[n++] = '0' + x % 10, x /= 10;
  while (n < output_len)
    s[n++] = '0';
  while (n--)
    writeChar(s[n]);
}

inline void writeWord(const char *s) {
  while (*s)
    writeChar(*s++);
}

inline void writeDouble(double x, int output_len) {
  if (x < 0)
    writeChar('-'), x = -x;
  int t = (int)x;
  writeUInt(t), x -= t;
  writeChar('.');
  for (int i = output_len - 1; i > 0; i--) {
    x *= 10;
    t = std::min(9, (int)x);
    writeChar('0' + t), x -= t;
  }
  x *= 10;
  t = std::min(9, (int)(x + 0.5));
  writeChar('0' + t);
}

using namespace std;

#define pb push_back

const int N = 5e5 + 10;
vector<int> t[4 * N];
int nex[N];

void build(int v, int l, int r) {
  if (l == r) {
    vector<int> kek;
    kek.pb(nex[l]);
    t[v] = kek;
    return;
  }
  int m = (l + r) / 2;
  build(2 * v, l, m), build(2 * v + 1, m + 1, r);
  int ll = 0, rr = 0;
  vector<int> c;
  for (int i = 0; i < t[v * 2].size() + t[v * 2 + 1].size(); i++) {
    if (ll == t[v * 2].size()) {
      t[v].pb(t[v * 2 + 1][rr++]);
      continue;
    }
    if (rr == t[v * 2 + 1].size()) {
      t[v].pb(t[v * 2][ll++]);
      continue;
    }
    if (t[v * 2][ll] < t[v * 2 + 1][rr]) {
      t[v].pb(t[v * 2][ll++]);
    } else {
      t[v].pb(t[v * 2 + 1][rr++]);
    }
  }
}

int get(int v, int tl, int tr, int l, int r, int val) {
  if (l > r)
    return 0;
  if (tl == l && tr == r) {
    int u = upper_bound(t[v].begin(), t[v].end(), val) - t[v].begin();
    return t[v].size() - u;
  }
  int tm = (tl + tr) / 2;
  return (get(2 * v, tl, tm, l, min(r, tm), val) +
          get(2 * v + 1, tm + 1, tr, max(l, tm + 1), r, val));
}

int32_t main() {
  int n, q, l, r;
  n = readInt();
  q = readInt();
  vector<int> v(n), last(n + 1, 1e9);
  for (int i = 0; i < n; ++i) {
    v[i] = readInt();
  }
  for (int i = n - 1; i > -1; --i) {
    nex[i] = last[v[i]];
    last[v[i]] = i;
  }
  build(1, 0, n - 1);
  q++;
  while (--q) {
    l = readInt();
    r = readInt();
    l--, r--;
    cout << get(1, 0, n - 1, l, r, r) << "\\n";
  }
  return 0;
}


Error: TLE

Fixed submission:

#include <algorithm>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <iostream>
#include <map>
#include <set>
#include <string>
#include <vector>

/** Interface */

template <class T = int> inline T readInt();
inline double readDouble();
inline int readUInt();
inline int readChar();
inline void readWord(char *s);
inline bool readLine(char *s); // do not save '\\n'
inline bool isEof();
inline int peekChar();
inline bool seekEof();

template <class T> inline void writeInt(T x, int len = -1);
template <class T> inline void writeUInt(T x, int len = -1);
inline void writeChar(int x);
inline void writeWord(const char *s);
inline void writeDouble(double x, int len = 0);
inline void flush();

/** Read */

static const int buf_size = 4096;

static char buf[buf_size];
static int buf_len = 0, buf_pos = 0;

inline bool isEof() {
  if (buf_pos == buf_len) {
    buf_pos = 0, buf_len = fread(buf, 1, buf_size, stdin);
    if (buf_pos == buf_len)
      return 1;
  }
  return 0;
}

inline int getChar() { return isEof() ? -1 : buf[buf_pos++]; }

inline int peekChar() { return isEof() ? -1 : buf[buf_pos]; }

inline bool seekEof() {
  int c;
  while ((c = peekChar()) != -1 && c <= 32)
    buf_pos++;
  return c == -1;
}

inline int readChar() {
  int c = getChar();
  while (c != -1 && c <= 32)
    c = getChar();
  return c;
}

inline int readUInt() {
  int c = readChar(), x = 0;
  while ('0' <= c && c <= '9')
    x = x * 10 + c - '0', c = getChar();
  return x;
}

template <class T> inline T readInt() {
  int s = 1, c = readChar();
  T x = 0;
  if (c == '-')
    s = -1, c = getChar();
  while ('0' <= c && c <= '9')
    x = x * 10 + c - '0', c = getChar();
  return s == 1 ? x : -x;
}

inline double readDouble() {
  int s = 1, c = readChar();
  double x = 0;
  if (c == '-')
    s = -1, c = getChar();
  while ('0' <= c && c <= '9')
    x = x * 10 + c - '0', c = getChar();
  if (c == '.') {
    c = getChar();
    double coef = 1;
    while ('0' <= c && c <= '9')
      x += (c - '0') * (coef *= 1e-1), c = getChar();
  }
  return s == 1 ? x : -x;
}

inline void readWord(char *s) {
  int c = readChar();
  while (c > 32)
    *s++ = c, c = getChar();
  *s = 0;
}

inline bool readLine(char *s) {
  int c = getChar();
  while (c != '\\n' && c != -1)
    *s++ = c, c = getChar();
  *s = 0;
  return c != -1;
}

/** Write */

static int write_buf_pos = 0;
static char write_buf[buf_size];

inline void writeChar(int x) {
  if (write_buf_pos == buf_size)
    fwrite(write_buf, 1, buf_size, stdout), write_buf_pos = 0;
  write_buf[write_buf_pos++] = x;
}

inline void flush() {
  if (write_buf_pos)
    fwrite(write_buf, 1, write_buf_pos, stdout), write_buf_pos = 0;
}

template <class T> inline void writeInt(T x, int output_len) {
  if (x < 0)
    writeChar('-'), x = -x;

  char s[24];
  int n = 0;
  while (x || !n)
    s[n++] = '0' + x % 10, x /= 10;
  while (n < output_len)
    s[n++] = '0';
  while (n--)
    writeChar(s[n]);
}

template <class T> inline void writeUInt(T x, int output_len) {
  char s[24];
  int n = 0;
  while (x || !n)
    s[n++] = '0' + x % 10, x /= 10;
  while (n < output_len)
    s[n++] = '0';
  while (n--)
    writeChar(s[n]);
}

inline void writeWord(const char *s) {
  while (*s)
    writeChar(*s++);
}

inline void writeDouble(double x, int output_len) {
  if (x < 0)
    writeChar('-'), x = -x;
  int t = (int)x;
  writeUInt(t), x -= t;
  writeChar('.');
  for (int i = output_len - 1; i > 0; i--) {
    x *= 10;
    t = std::min(9, (int)x);
    writeChar('0' + t), x -= t;
  }
  x *= 10;
  t = std::min(9, (int)(x + 0.5));
  writeChar('0' + t);
}

using namespace std;

#define pb push_back

const int N = 5e5 + 10;
vector<int> t[4 * N];
int nex[N];

void build(int v, int l, int r) {
  if (l == r) {
    vector<int> kek;
    kek.pb(nex[l]);
    t[v] = kek;
    return;
  }
  int m = (l + r) / 2;
  build(2 * v, l, m), build(2 * v + 1, m + 1, r);
  int ll = 0, rr = 0;
  vector<int> c;
  for (int i = 0; i < t[v * 2].size() + t[v * 2 + 1].size(); i++) {
    if (ll == t[v * 2].size()) {
      t[v].pb(t[v * 2 + 1][rr++]);
      continue;
    }
    if (rr == t[v * 2 + 1].size()) {
      t[v].pb(t[v * 2][ll++]);
      continue;
    }
    if (t[v * 2][ll] < t[v * 2 + 1][rr]) {
      t[v].pb(t[v * 2][ll++]);
    } else {
      t[v].pb(t[v * 2 + 1][rr++]);
    }
  }
}

int get(int v, int tl, int tr, int l, int r, int val) {
  if (l > r)
    return 0;
  if (tl == l && tr == r) {
    int u = upper_bound(t[v].begin(), t[v].end(), val) - t[v].begin();
    return t[v].size() - u;
  }
  int tm = (tl + tr) / 2;
  return (get(2 * v, tl, tm, l, min(r, tm), val) +
          get(2 * v + 1, tm + 1, tr, max(l, tm + 1), r, val));
}

int32_t main() {
  int n, q;
  n = readInt();
  q = readInt();
  vector<int> v(n);
  map<int, int> last;
  for (int i = 0; i < n; i++) {
    v[i] = readInt();
    last[v[i]] = 1e9;
  }
  for (int i = n - 1; i > -1; i--) {
    nex[i] = last[v[i]];
    last[v[i]] = i;
  }
  build(1, 0, n - 1);
  q++;
  while (--q) {
    int l, r;
    l = readInt();
    r = readInt();
    l--, r--;
    cout << get(1, 0, n - 1, l, r, r) << "\\n";
  }
  return 0;
}