oj.uz

Submission #1000173

# Submission time Handle Problem Language Result Execution time Memory
1000173 2024-06-16T21:27:42 Z whatthemomooofun1729 Sorting (IOI15_sorting) C++17
100 / 100
 139 ms 23772 KB 
#include <iostream>
#include <algorithm>
#include <utility>
#include <vector>
#include <stack>
#include <map>
#include <queue>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cstring>
#include <cmath>
#include <functional>
#include <cassert>
#include <iomanip>
#include <numeric>
#include <bitset>
#include <sstream>
#include <chrono>
#include <random>

#define ff first
#define ss second
#define PB push_back
#define sz(x) int(x.size())
#define rsz resize
#define fch(xxx, yyy) for (auto xxx : yyy) // abusive notation
#define all(x) (x).begin(),(x).end()
#define eps 1e-9

// more abusive notation (use at your own risk):
//#define int ll

using namespace std;
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using vi = vector<int>;
using vll = vector<ll>;

// debugging
void __print(int x) {std::cerr << x;}
void __print(ll x) {std::cerr << x;} /* remember to uncomment this when not using THE MACRO */
void __print(unsigned x) {std::cerr << x;}
void __print(ull x) {std::cerr << x;}
void __print(float x) {std::cerr << x;}
void __print(double x) {std::cerr << x;}
void __print(ld x) {std::cerr << x;}
void __print(char x) {std::cerr << '\'' << x << '\'';}
void __print(const char *x) {std::cerr << '\"' << x << '\"';}
void __print(const string& x) {std::cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V> void __print(const pair<T, V> &x) {std::cerr << '{'; __print(x.ff); std::cerr << ", "; __print(x.ss); std::cerr << '}';}
template<typename T> void __print(const T& x) {int f = 0; std::cerr << '{'; for (auto &i: x) std::cerr << (f++ ? ", " : ""), __print(i); std::cerr << "}";}
void _print() {std::cerr << "]\n";}
template <typename T, typename... V> void _print(T t, V... v) {__print(t); if (sizeof...(v)) std::cerr << ", "; _print(v...);}
void println() {std::cerr << ">--------------------<" << endl;}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

// templates
template <class T> bool ckmin(T &a, const T &b) {return b<a ? a = b, 1 : 0;}
template <class T> bool ckmax(T &a, const T &b) {return b>a ? a = b, 1 : 0;}
template <class T> using gr = greater<T>;
template <class T> using vc = vector<T>;
template <class T> using p_q = priority_queue<T>;
template <class T> using pqg = priority_queue<T, vc<T>, gr<T>>;
template <class T1, class T2> using pr = pair<T1, T2>;
mt19937_64 rng_ll(chrono::steady_clock::now().time_since_epoch().count());
int rng(int M) {return (int)(rng_ll()%M);} /*returns any random number in [0, M) */

// const variables
constexpr int INF = (int)2e9;
constexpr int MOD = 998244353;
constexpr ll LL_INF = (ll)3e18;
constexpr int mod = (int)1e9 + 7;
constexpr ll inverse = 500000004LL; // inverse of 2 modulo 1e9 + 7

void setIO(const string& str) {// fast input/output
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (str.empty()) return;
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
}

vc<pii> findOperations(vector<int> v) {
    int N = sz(v);
    vc<pii> ops;
    vi idx(N);
    for (int i = 0; i < N; ++i) {
        idx[v[i]] = i;
    }
//    debug(v);
//    debug(idx);
    for (int i = 0; i < N; ++i) {
        // place i here
//        debug(i);
//        debug(idx);
        if (idx[i] != i) {
            int a = i, b = idx[i];
//            debug(a, b);
            ops.PB({a, b});
            swap(idx[i], idx[v[i]]);
            swap(v[a], v[b]);
        }
    }
//    debug(v);
    reverse(all(ops));
    return ops;
}

int findSwapPairs(int N, int* s, int M, int* x, int* y, int* p, int* q) {
    vc<pii> ans; // answer (the set of operations needed)
    int l = 0, r = M; // bounds on binary search
    // note that the array can already be sorted, so l is within [0, M]
    while (l <= r) {
        int mid = (l + r) / 2; // assume that 'mid' moves are taken
        vi v(N);
        for (int i = 0; i < N; ++i) {
            v[i] = s[i]; // stores the apples in their original order on the plates from 0 to N - 1
        }
        for (int i = 0; i < mid; ++i) { // O(LogM)
            swap(v[x[i]], v[y[i]]); // now, swap the apples
        }
        vc<pii> ops = findOperations(v); // operations that make Aizhan win
        // ops -> swap the plates under the apples
        // if we end up with some permutation [v[0], ... v[N]]
        // we want the plates to be in that same orientation
        // or, we change [v[0], ... v[N]] -> [0, 1, 2, ... N] (1)
        // if we do (1), we need to reverse the list of operations before outputting
        if (sz(ops) <= mid) {
            r = mid - 1;
        } else {
            l = mid + 1;
        }
    }
    r++;
    // redo the above operations
    vi v(N);
    for (int i = 0; i < N; ++i) {
        v[i] = s[i];
    }
    for (int i = 0; i < r; ++i) {
        swap(v[x[i]], v[y[i]]);
    }
    ans = findOperations(v);
    // fill the rest of the operations if needed
    while (sz(ans) < r) {
        ans.PB({0, 0});
    }
    vi idx(N); // finding the index of an element a[i] in the array
    for (int i = 0; i < N; ++i) {
        idx[s[i]] = i;
        v[i] = s[i]; // resetting v
    }
    for (int i = 0; i < r; ++i) {
        swap(v[x[i]], v[y[i]]); // performing swap operations for Ermek
    }
    for (int i = 0; i < r; ++i) { // performing the swap operations for Aizhan
        swap(idx[s[x[i]]], idx[s[y[i]]]);
        swap(s[x[i]], s[y[i]]);
        // v[ans[i].ff] and v[ans[i].ss] are the apples corresponding to the plates that need to be flipped
        // idx[v[ans[i].ff]] and idx[v[ans[i].ss]] are the plates corresponding to the apples in the current array
        p[i] = idx[v[ans[i].ff]], q[i] = idx[v[ans[i].ss]]; // convert each swap to the index it is currently in and add it to (p, q)
        swap(idx[s[p[i]]], idx[s[q[i]]]); // flip/update
        swap(s[p[i]], s[q[i]]);
    }
    return r;
}

void solve() { // testing cases for this algorithm
    int N, M;
    int s[100005], x[100005], y[100005], p[100005], q[100005];
    cin >> N >> M;
    for (int i = 0; i < N; ++i) {
        cin >> s[i];
    }
    for (int i = 0; i < M; ++i) {
        cin >> x[i] >> y[i];
    }
    vi v(N);
    for (int i = 0; i < N; ++i) {
        v[i] = s[i];
    }
    int moves = findSwapPairs(N, s, M, x, y, p, q);
    cout << moves << '\n';
    for (int i = 0; i < moves; ++i) {
        cout << p[i] << ' ' << q[i] << '\n';
    }
    for (int i = 0; i < moves; ++i) {
        swap(v[x[i]], v[y[i]]);
        swap(v[p[i]], v[q[i]]);
    }
    cout << "resulting array: \n";
    for (int i = 0; i < N; ++i) {
        cout << v[i] << ' ';
    }
    cout << '\n';
}
/*
signed main() { // TIME YOURSELF !!!
    setIO("");
    solve();
}*/

// TLE -> TRY NOT USING DEFINE INT LONG LONG
// CE -> CHECK LINE 45
// 5000 * 5000 size matrices are kinda big (potential mle)
// Do something, start simpler

Compilation message

sorting.cpp: In function 'void setIO(const string&)':
sorting.cpp:88:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sorting.cpp:89:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 600 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 600 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 344 KB Output is correct
12 Correct 0 ms 348 KB Output is correct

Subtask #3
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 600 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 344 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 1 ms 348 KB Output is correct
22 Correct 1 ms 344 KB Output is correct
23 Correct 1 ms 348 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 1 ms 348 KB Output is correct
26 Correct 1 ms 348 KB Output is correct
27 Correct 1 ms 348 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 344 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct

Subtask #6
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 344 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 115 ms 12336 KB Output is correct
16 Correct 133 ms 20232 KB Output is correct
17 Correct 133 ms 21108 KB Output is correct
18 Correct 52 ms 18632 KB Output is correct
19 Correct 100 ms 19752 KB Output is correct
20 Correct 130 ms 21364 KB Output is correct
21 Correct 106 ms 20068 KB Output is correct
22 Correct 110 ms 18096 KB Output is correct
23 Correct 122 ms 21952 KB Output is correct
24 Correct 132 ms 21712 KB Output is correct
25 Correct 134 ms 22720 KB Output is correct
26 Correct 100 ms 19588 KB Output is correct
27 Correct 93 ms 18960 KB Output is correct
28 Correct 127 ms 21652 KB Output is correct
29 Correct 139 ms 22688 KB Output is correct
30 Correct 77 ms 18112 KB Output is correct
31 Correct 128 ms 21480 KB Output is correct
32 Correct 123 ms 21148 KB Output is correct
33 Correct 133 ms 21460 KB Output is correct
34 Correct 127 ms 21560 KB Output is correct
35 Correct 108 ms 20652 KB Output is correct
36 Correct 46 ms 16788 KB Output is correct
37 Correct 137 ms 23772 KB Output is correct
38 Correct 134 ms 21404 KB Output is correct
39 Correct 132 ms 22824 KB Output is correct