Problem p01360 (C++) — buggy submission, verdict: Memory Limit Exceeded

#include <algorithm>
#include <bitset>
#include <cassert>
#include <climits>
#include <cmath>
#include <complex>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <fstream>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;
#define REP(i, n) for (int(i) = 0; (i) < (n); (i)++)
#define FOR(i, a, b) for (int(i) = (a); (i) < (b); (i)++)
#define RREP(i, a) for (int(i) = (a)-1; (i) >= 0; (i)--)
#define FORR(i, a, b) for (int(i) = (a)-1; (i) >= (b); (i)--)
#define DEBUG(C) cerr << #C << " = " << C << endl;
using LL = long long;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<LL>;
using VVL = vector<VL>;
using VD = vector<double>;
using VVD = vector<VD>;
using PII = pair<int, int>;
using PDD = pair<double, double>;
using PLL = pair<LL, LL>;
using VPII = vector<PII>;
template <typename T> using VT = vector<T>;
#define ALL(a) begin((a)), end((a))
#define RALL(a) rbegin((a)), rend((a))
#define SORT(a) sort(ALL((a)))
#define RSORT(a) sort(RALL((a)))
#define REVERSE(a) reverse(ALL((a)))
#define MP make_pair
#define FORE(a, b) for (auto &&a : (b))
#define FIND(s, e) ((s).find(e) != (s).end())
#define EB emplace_back
template <typename T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}

const int INF = 1e9;
const int MOD = INF + 7;
const LL LLINF = 1e18;
const double EPS = 1e-9;

/*
 7 8 9
 4   6
 1 2 3
*/

void init() {}

const int MAX = 1e5 + 10;
int dp[9][9][2], newdp[9][9][2];
void solve(string s) {
  for (int j = 0; j < 9; j++) {
    for (int k = 0; k < 9; k++) {
      for (int l = 0; l < 2; l++) {
        dp[j][k][l] = INF;
        newdp[j][k][l] = INF;
      }
    }
  }
  for (int i = 0; i < 9; i++) {
    for (int j = 0; j < 9; j++) {
      if (i % 3 > j % 3)
        continue;
      if (i == 4 || j == 4)
        continue;
      for (int k = 0; k < 2; k++) {
        dp[i][j][k] = 0;
      }
    }
  }
  const int L = s.length();
  for (int i = 0; i < L; i++) {
    const int nxt = (s[i] - '0') - 1;
    for (int j = 0; j < 9; j++) { //???
      if (j == 4)
        continue;
      for (int k = 0; k < 9; k++) { //???
        if (k == 4)
          continue;
        if (j % 3 <= nxt % 3) {
          chmin(newdp[j][nxt][0], dp[j][k][1]);
        } else {
          chmin(newdp[nxt][k][1], dp[j][k][1] + 1);
        }
        if (nxt % 3 <= k % 3) {
          chmin(newdp[nxt][k][1], dp[j][k][0]);
        } else {
          chmin(newdp[j][nxt][0], dp[j][k][0] + 1);
        }
      }
    }
    for (int j = 0; j < 9; j++) {
      for (int k = 0; k < 9; k++) {
        for (int l = 0; l < 2; l++) {
          dp[j][k][l] = newdp[j][k][l];
          newdp[j][k][l] = INF;
        }
      }
    }
  }
  int ans = INF;
  for (int i = 0; i < 9; i++) {
    for (int j = 0; j < 9; j++) {
      for (int k = 0; k < 2; k++) {
        chmin(ans, dp[i][j][k]);
      }
    }
  }
  printf("%d\\n", ans);
}

signed main(void) {
  LL n, m, p, a, b, c, x, y, z, q;
  string s;
  bool f = false;
  init();
  while (cin >> s, s != "#") {
    solve(s);
  }
}

Error: MLE

Fixed submission:

#include <algorithm>
#include <bitset>
#include <cassert>
#include <climits>
#include <cmath>
#include <complex>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <fstream>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;
#define REP(i, n) for (int(i) = 0; (i) < (n); (i)++)
#define FOR(i, a, b) for (int(i) = (a); (i) < (b); (i)++)
#define RREP(i, a) for (int(i) = (a)-1; (i) >= 0; (i)--)
#define FORR(i, a, b) for (int(i) = (a)-1; (i) >= (b); (i)--)
#define DEBUG(C) cerr << #C << " = " << C << endl;
using LL = long long;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<LL>;
using VVL = vector<VL>;
using VD = vector<double>;
using VVD = vector<VD>;
using PII = pair<int, int>;
using PDD = pair<double, double>;
using PLL = pair<LL, LL>;
using VPII = vector<PII>;
template <typename T> using VT = vector<T>;
#define ALL(a) begin((a)), end((a))
#define RALL(a) rbegin((a)), rend((a))
#define SORT(a) sort(ALL((a)))
#define RSORT(a) sort(RALL((a)))
#define REVERSE(a) reverse(ALL((a)))
#define MP make_pair
#define FORE(a, b) for (auto &&a : (b))
#define FIND(s, e) ((s).find(e) != (s).end())
#define EB emplace_back
template <typename T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}

const int INF = 1e9;
const int MOD = INF + 7;
const LL LLINF = 1e18;
const double EPS = 1e-9;

/*
 7 8 9
 4   6
 1 2 3
*/

void init() {}

const int MAX = 1e5 + 10;
int dp[MAX][9][9][2];
void solve(string s) {
  for (int i = 0; i < MAX; i++) {
    for (int j = 0; j < 9; j++) {
      for (int k = 0; k < 9; k++) {
        for (int l = 0; l < 2; l++) {
          dp[i][j][k][l] = INF;
        }
      }
    }
  }
  for (int i = 0; i < 9; i++) {
    for (int j = 0; j < 9; j++) {
      if (i % 3 > j % 3)
        continue;
      if (i == 4 || j == 4)
        continue;
      for (int k = 0; k < 2; k++) {
        dp[0][i][j][k] = 0;
      }
    }
  }
  const int L = s.length();
  for (int i = 0; i < L; i++) {
    const int nxt = (s[i] - '0') - 1;
    for (int j = 0; j < 9; j++) { //???
      if (j == 4)
        continue;
      for (int k = 0; k < 9; k++) { //???
        if (k == 4)
          continue;
        if (j % 3 <= nxt % 3) {
          chmin(dp[i + 1][j][nxt][0], dp[i][j][k][1]);
        } else {
          chmin(dp[i + 1][nxt][k][1], dp[i][j][k][1] + 1);
        }
        if (nxt % 3 <= k % 3) {
          chmin(dp[i + 1][nxt][k][1], dp[i][j][k][0]);
        } else {
          chmin(dp[i + 1][j][nxt][0], dp[i][j][k][0] + 1);
        }
      }
    }
  }
  int ans = INF;
  for (int i = 0; i < 9; i++) {
    for (int j = 0; j < 9; j++) {
      for (int k = 0; k < 2; k++) {
        chmin(ans, dp[L][i][j][k]);
      }
    }
  }
  printf("%d\\n", ans);
}

signed main(void) {
  LL n, m, p, a, b, c, x, y, z, q;
  string s;
  bool f = false;
  init();
  while (cin >> s, s != "#") {
    solve(s);
  }
}