Author : Dipu Kumar Mohanto
CSE, Batch - 6
BRUR.
Problem Statement : Sofdor Ali and Bracket Sequence
Source : toph.co
Category : String, Data Structure
Algorithm : Suffix Array, Segment Tree
Verdict : Accepted
- #include "bits/stdc++.h"
-
- using namespace std;
-
- #define FI freopen("in.txt", "r", stdin)
- #define FO freopen("out.txt", "w", stdout)
- #define FAST ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL)
-
- #define FOR(i, n) for (int i = 1; i <= n; i++)
- #define For(i, n) for (int i = 0; i < n; i++)
- #define ROF(i, n) for (int i = n; i >= 1; i--)
- #define Rof(i, n) for (int i = n-1; i >= 0; i--)
- #define FORI(i, n) for (auto i : n)
- #define REP(i, a, b) for (int i = a; i <= b; i++)
-
- #define ll long long
- #define ull unsigned long long
- #define vi vector <int>
- #define vl vector <ll>
- #define pii pair <int, int>
- #define pll pair <ll, ll>
- #define mk make_pair
- #define ff first
- #define ss second
- #define eb emplace_back
- #define em emplace
- #define pb push_back
- #define ppb pop_back
- #define All(a) a.begin(), a.end()
- #define memo(a, b) memset(a, b, sizeof a)
- #define Sort(a) sort(All(a))
- #define ED(a) Sort(a), a.erase(unique(All(a)), a.end())
- #define rev(a) reverse(All(a))
- #define sz(a) (int)a.size()
- #define max3(a, b, c) max(a, max(b, c))
- #define min3(a, b, c) min(a, min(b, c))
- #define maxAll(a) *max_element(All(a))
- #define minAll(a) *min_element(All(a))
- #define allUpper(a) transform(All(a), a.begin(), :: toupper)
- #define allLower(a) transform(All(a), a.begin(), :: tolower)
- #define endl '\n'
- #define nl puts("")
- #define ub upper_bound
- #define lb lower_bound
- #define Exp exp(1.0)
- #define PIE 2*acos(0.0)
- #define Sin(a) sin(((a)*PIE)/180.0)
- #define EPS 1e-9
-
- #include "ext/pb_ds/assoc_container.hpp"
- #include "ext/pb_ds/tree_policy.hpp"
- using namespace __gnu_pbds;
-
- template <typename T> using orderset = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;
-
- #include "ext/rope"
- using namespace __gnu_cxx;
-
-
-
-
-
-
-
-
-
-
- #define trace1(x) cerr << #x << ": " << x << endl;
- #define trace2(x, y) cerr << #x << ": " << x << " | " << #y << ": " << y << endl;
- #define trace3(x, y, z) cerr << #x << ": " << x << " | " << #y << ": " << y << " | " << #z << ": " << z << endl;
- #define trace4(a, b, c, d) cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": " << c << " | " << #d << ": " << d << endl;
- #define trace5(a, b, c, d, e) cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": " << c << " | " << #d << ": " << d << " | " << #e << ": " << e << endl;
- #define trace6(a, b, c, d, e, f) cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": " << c << " | " << #d << ": " << d << " | " << #e << ": " << e << " | " << #f << ": " << f << endl;
-
- inline int setbit(int mask, int pos) { return mask |= (1 << pos); }
- inline int resetbit(int mask, int pos) { return mask &= ~(1 << pos); }
- inline int togglebit(int mask, int pos) { return mask ^= (1 << pos); }
- inline bool checkbit(int mask, int pos) { return (bool)(mask & (1 << pos)); }
-
- #define popcount(mask) __builtin_popcount(mask) // count set bit
- #define popcountLL(mask) __builtin_popcountll(mask) // for long long
-
- inline int read() { int a; scanf("%d", &a); return a; }
- inline ll readLL() { ll a; scanf("%lld", &a); return a; }
- inline double readDD() { double a; scanf("%lf", &a); return a; }
-
- template <typename T> string toString(T num) { stringstream ss; ss << num; return ss.str(); }
- int toInt(string s) { int num; istringstream iss(s); iss >> num; return num; }
- ll toLLong(string s) { ll num; istringstream iss(s); iss >> num; return num; }
-
- #define inf 1e7
- #define mod 1000000007
-
- static const int maxn = 2e5 + 5;
- static const int logn = 21;
-
- struct segmentTree
- {
- int open, close;
- segmentTree(int open = 0, int close = 0) :
- open(open), close(close) {}
-
- inline void assignLeaf(char ch)
- {
- open = close = 0;
- if (ch == '(') ++open;
- else ++close;
- }
- inline void marge(const segmentTree &lft, const segmentTree &rgt)
- {
- int mini = min(lft.open, rgt.close);
- open = lft.open + rgt.open - mini;
- close = lft.close + rgt.close - mini;
- }
- inline bool balanced()
- {
- return (open == 0 && close == 0);
- }
- } Tree[maxn << 2];
-
- string s;
- bool balancedPos[maxn];
-
- inline void build(int node, int a, int b)
- {
- if (a == b)
- {
- Tree[node].assignLeaf(s[a-1]);
- return;
- }
- int lft = node << 1;
- int rgt = lft | 1;
- int mid = (a + b) >> 1;
- build(lft, a, mid);
- build(rgt, mid+1, b);
- Tree[node].marge(Tree[lft], Tree[rgt]);
- }
-
- inline segmentTree query(int node, int a, int b, int i, int j)
- {
- if (a == i && b == j) return Tree[node];
- int lft = node << 1;
- int rgt = lft | 1;
- int mid = (a + b) >> 1;
- segmentTree res = segmentTree();
- if (j <= mid)
- {
- segmentTree p = query(lft, a, mid, i, j);
- res.marge(res, p);
- }
- else if (i > mid)
- {
- segmentTree q = query(rgt, mid+1, b, i, j);
- res.marge(res, q);
- }
- else
- {
- segmentTree p = query(lft, a, mid, i, mid);
- segmentTree q = query(rgt, mid+1, b, mid+1, j);
- res.marge(res, p);
- res.marge(res, q);
- }
- return res;
- }
-
- struct entry
- {
- int first, second;
- int p;
- entry(int ff = 0, int ss = 0, int pp = 0) : first(ff), second(ss), p(pp) {}
- friend bool operator < (const entry &A, const entry &B)
- {
- if (A.first == B.first) return A.second < B.second;
- return A.first < B.first;
- }
- } L[maxn];
-
- int P[logn][maxn], B[maxn];
- int p, q;
- int step, lcp[maxn];
-
- inline int comp2(const int &a, const int &b)
- {
- return P[step-1][a] < P[step-1][b];
- }
-
- inline void suffixArray(const string &s)
- {
- int len = s.size();
- for (int i = 0; i < len; i++) P[0][i] = s[i] - '0';
- step = 1;
- int cnt = 1;
- for ( ; cnt>>1 < len; step++, cnt <<= 1)
- {
- for (int i = 0; i < len; i++)
- {
- L[i].first = P[step-1][i];
- L[i].second = (i + cnt) < len ? P[step-1][i+cnt] : -1;
- L[i].p = i;
- }
- sort(L, L+len);
- for (int i = 0; i < len; i++)
- {
- if (i > 0 && L[i].first == L[i-1].first && L[i].second == L[i-1].second)
- P[step][ L[i].p ] = P[step][ L[i-1].p ];
- else
- P[step][ L[i].p ] = i;
- }
- }
- for (int i = 0; i < len; i++) B[i] = i;
- sort(B, B+len, comp2);
- }
-
- int main()
- {
-
- FAST;
- cin >> s;
- int len = sz(s);
- if (len & 1)
- {
- cout << "-1\n";
- exit(0);
- }
- s += s;
- int n = sz(s);
- build(1, 1, n);
- bool exist = 0;
- for (int i = 1; i <= len; i++)
- {
- segmentTree q = query(1, 1, n, i, i+len-1);
- if (q.balanced()) exist = 1, balancedPos[i-1] = 1;
- }
- if (exist == 0)
- {
- cout << "-1\n";
- exit(0);
- }
- suffixArray(s);
- for (int i = 0; i < n; i++)
- {
- if (balancedPos[ B[i] ])
- {
- cout << s.substr(B[i], len) << endl;
- break;
- }
- }
- }
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