CSES - Datatähti 2024 alku - Results
Submission details
Task:Käännöt
Sender:chaotic
Submission time:2023-11-11 18:21:51 +0200
Language:C++20
Status:READY
Result:100
Feedback
groupverdictscore
#1ACCEPTED13
#2ACCEPTED19
#3ACCEPTED33
#4ACCEPTED35
Test results
testverdicttimegroup
#1ACCEPTED0.00 s1details
#2ACCEPTED0.00 s1details
#3ACCEPTED0.00 s1details
#4ACCEPTED0.00 s1details
#5ACCEPTED0.00 s1details
#6ACCEPTED0.00 s2details
#7ACCEPTED0.00 s2details
#8ACCEPTED0.00 s2details
#9ACCEPTED0.00 s2details
#10ACCEPTED0.00 s2details
#11ACCEPTED0.01 s2details
#12ACCEPTED0.01 s2details
#13ACCEPTED0.01 s2details
#14ACCEPTED0.01 s2details
#15ACCEPTED0.00 s2details
#16ACCEPTED0.01 s2details
#17ACCEPTED0.00 s3details
#18ACCEPTED0.00 s3details
#19ACCEPTED0.01 s3details
#20ACCEPTED0.01 s3details
#21ACCEPTED0.01 s3details
#22ACCEPTED0.01 s3details
#23ACCEPTED0.01 s3details
#24ACCEPTED0.00 s3details
#25ACCEPTED0.01 s3details
#26ACCEPTED0.00 s4details
#27ACCEPTED0.00 s4details
#28ACCEPTED0.01 s4details
#29ACCEPTED0.01 s4details
#30ACCEPTED0.01 s4details
#31ACCEPTED0.01 s4details
#32ACCEPTED0.00 s4details
#33ACCEPTED0.01 s4details
#34ACCEPTED0.01 s4details

Code

#include <algorithm>
#include <cassert>
#include <iostream>
#include <map>
#include <ranges>
#include <sstream>
#include <string>
#include <vector>

auto sort_2(std::vector<int>& values) {
    std::vector<size_t> operations;
    operations.reserve(100000);

    // Swaps idx and idx+1
    auto swap = [&](size_t idx) {
        std::swap(values[idx], values[idx + 1]);
        operations.push_back(idx);
    };

    size_t remaining = values.size();

    while (remaining != 0) {
        size_t idx =
            std::ranges::find(values | std::views::take(remaining), remaining) - values.begin();

        for (; idx != remaining - 1; ++idx) { swap(idx); }
        --remaining;
    }

    return std::tuple(true, operations);
}

std::tuple<bool, std::vector<size_t>> sort_3(std::vector<int>& values) {
    // Check
    // values[i] % 2 should be 1
    for (size_t i = 0; i < values.size(); ++i) {
        if ((values[i] - i) % 2 != 1) return {false, {}};
    }

    std::vector<size_t> operations;
    operations.reserve(100000);

    // Swaps idx and idx+2
    auto swap = [&](size_t idx) {
        std::swap(values[idx], values[idx + 2]);
        operations.push_back(idx);
    };

    size_t remaining = values.size();

    while (remaining != 0) {
        size_t idx =
            std::ranges::find(values | std::views::take(remaining), remaining) - values.begin();

        for (; idx != remaining - 1; idx += 2) { swap(idx); }
        --remaining;
    }

    return {true, operations};
}

struct op_4 {
    size_t min_list_len;
    std::vector<size_t> indices;
};
inline constexpr size_t unsortable = -1;

// There are 24 4-long lists
inline std::map<std::array<int, 4>, op_4> const sort_4_map = {
    {{1, 2, 3, 4}, {4, {}}                         },
    {{1, 2, 4, 3}, {unsortable, {}}                },
    {{1, 3, 2, 4}, {unsortable, {}}                },
    {{1, 3, 4, 2}, {6, {0, 2, 1, 2, 1, 0, 2, 0, 1}}},
    {{1, 4, 2, 3}, {6, {0, 2, 1, 0, 1, 0, 1, 2, 1}}},
    {{1, 4, 3, 2}, {unsortable, {}}                },
    {{2, 1, 3, 4}, {unsortable, {}}                },
    {{2, 1, 4, 3}, {6, {2, 1, 2, 0, 2, 1, 2}}      },
    {{2, 3, 1, 4}, {6, {1, 2, 1, 2, 0, 1, 0, 2}}   },
    {{2, 3, 4, 1}, {unsortable, {}}                },
    {{2, 4, 1, 3}, {unsortable, {}}                },
    {{2, 4, 3, 1}, {6, {2, 1, 2, 1, 0, 2, 0, 1}}   },
    {{3, 1, 2, 4}, {6, {2, 0, 1, 0, 2, 1, 2, 1}}   },
    {{3, 1, 4, 2}, {unsortable, {}}                },
    {{3, 2, 1, 4}, {unsortable, {}}                },
    {{3, 2, 4, 1}, {6, {2, 0, 1, 0, 1, 0, 2, 1}}   },
    {{3, 4, 1, 2}, {6, {2, 1, 0, 2, 0, 1, 2, 0}}   },
    {{3, 4, 2, 1}, {unsortable, {}}                },
    {{4, 1, 2, 3}, {unsortable, {}}                },
    {{4, 1, 3, 2}, {6, {1, 2, 0, 1, 2, 1, 2, 1}}   },
    {{4, 2, 1, 3}, {6, {1, 2, 1, 0, 1, 0, 1, 2}}   },
    {{4, 2, 3, 1}, {unsortable, {}}                },
    {{4, 3, 1, 2}, {unsortable, {}}                },
    {{4, 3, 2, 1}, {4, {0}}                        },
};

std::tuple<bool, std::vector<size_t>> sort_4(std::vector<int>& values) {
    // First sort the list except first 4 elements
    std::vector<size_t> operations;
    operations.reserve(100000);

    // Swaps idx and idx+2
    auto swap = [&](size_t idx) {
        std::swap(values[idx], values[idx + 3]);
        std::swap(values[idx + 1], values[idx + 2]);
        operations.push_back(idx);
    };

    size_t value = values.size();

    for (; value != 4; --value) {
        size_t idx = std::ranges::find(values | std::views::take(value), value) - values.begin();

        // Move this one to the back
        int distance = value - (idx + 1);
        assert(distance >= 0);
        if (distance == 0) continue;

        // Align distance to 0 mod 3
        // Afterwards idx = pos o felement
        switch (distance % 3) {
        case 1: {
            if (distance != 1) {
                swap(idx);
                idx += 3;
            }
            swap(idx - 2);
            swap(idx - 3);
            idx -= 2;
            break;
        }
        case 2: {
            if (distance != 2) {
                swap(idx);
                idx += 3;
            }
            swap(idx - 2);
            idx -= 1;
            break;
        }
        }

        distance = value - (idx + 1);
        assert(distance % 3 == 0);

        // Move by multiplies of 3
        int times = distance / 3;
        for (int i = 0; i < times; ++i) {
            swap(idx);
            idx += 3;
        }
        assert(values[value - 1] == int(value));
    }

    // Sort first 4 elements
    std::array<int, 4> first4 = {values[0], values[1], values[2], values[3]};
    auto& info                = sort_4_map.at(first4);

    if (info.min_list_len > values.size()) { return {false, {}}; }
    operations.insert(operations.end(), info.indices.begin(), info.indices.end());

    return {true, operations};
}

using op_5 = op_4;

std::map<std::array<int, 5>, op_5> sort_5_map = {
    {{
         1,
         2,
         3,
         4,
         5,
     }, {5, {}}},
    {{
         1,
         4,
         5,
         2,
         3,
     }, {7,
      {
          1,
          2,
          0,
          2,
          0,
      }}},
    {{
         3,
         2,
         5,
         4,
         1,
     }, {7,
      {
          2,
          0,
          2,
          1,
      }}},
    {{
         3,
         4,
         1,
         2,
         5,
     }, {7,
      {
          0,
          1,
          2,
          0,
          2,
      }}},
    {{
         5,
         2,
         1,
         4,
         3,
     }, {7,
      {
          1,
          2,
          0,
          2,
      }}},
    {{
         5,
         4,
         3,
         2,
         1,
     }, {5,
      {
          0,
      }}},
};

std::tuple<bool, std::vector<size_t>> sort_5(std::vector<int>& values) {
    for (size_t i = 0; i < values.size(); ++i) {
        if ((values[i] - i) % 2 != 1) return {false, {}};
    }

    // First sort the list except first 4 elements
    std::vector<size_t> operations;
    operations.reserve(100000);

    // Swaps idx and idx+2
    auto swap = [&](size_t idx) {
        std::swap(values[idx], values[idx + 4]);
        std::swap(values[idx + 1], values[idx + 3]);
        operations.push_back(idx);
    };

    size_t value = values.size();
    for (; value != 5; --value) {
        size_t idx = std::ranges::find(values | std::views::take(value), value) - values.begin();

        int distance = value - (idx + 1);
        assert(distance >= 0);
        if (distance == 0) continue;

        // Align to a multiple of 4
        // 1 and 3 are impossible and should be already checked
        switch (distance % 4) {
        case 1: assert(false);
        case 2: {
            if (distance != 2) {
                swap(idx);
                idx += 4;
            }
            swap(idx - 3);
            idx -= 2;
            break;
        }
        case 3: assert(false);
        }

        distance = value - (idx + 1);
        assert(distance % 4 == 0);

        int times = distance / 4;
        for (int i = 0; i < times; ++i) {
            swap(idx);
            idx += 4;
        }
    }

    // Sort first 5 elements
    std::array<int, 5> first5 = {values[0], values[1], values[2], values[3], values[4]};
    auto it                   = sort_5_map.find(first5);
    if (it == sort_5_map.end()) { return {false, {}}; }
    auto& info = it->second;

    operations.insert(operations.end(), info.indices.begin(), info.indices.end());

    return {true, operations};
}

int main() {
    //    std::istringstream input(R"(5 3
    // 3 4 1 2 5)");
    auto& input = std::cin;

    size_t len;
    int k;
    input >> len >> k;

    std::vector<int> values;
    values.reserve(len);
    for (size_t i = 0; i < len; ++i) {
        int n;
        input >> n;
        values.push_back(n);
    }

    std::tuple<bool, std::vector<size_t>> res;
    switch (k) {
    case 2: res = sort_2(values); break;
    case 3: res = sort_3(values); break;
    case 4: {
        res = sort_4(values);
        //        for (auto x: values) std::cout << x << ", ";
        //        std::cout << "\n";
        break;
    }
    case 5: {
        res = sort_5(values);
        //        for (auto x: values) std::cout << x << ", ";
        //        std::cout << "\n";
        break;
    }
    }

    auto& [possible, vec] = res;

    if (!possible) {
        std::cout << "NO\n";
        return 0;
    } else {
        std::cout << "YES\n";
        std::cout << vec.size() << "\n";
        for (auto const& val: vec) { std::cout << val + 1 << ' '; }
        std::cout << "\n";
    }
}

Test details

Test 1

Group: 1

Verdict: ACCEPTED

input
5 2
1 2 3 4 5

correct output
YES
0

user output
YES
0

Test 2

Group: 1

Verdict: ACCEPTED

input
5 2
2 1 3 4 5

correct output
YES
1
1

user output
YES
1

Test 3

Group: 1

Verdict: ACCEPTED

input
20 2
6 20 18 2 16 13 19 17 8 14 11 ...

correct output
YES
366
2 3 4 5 6 7 8 9 10 11 12 13 14...

user output
YES
132
2 3 4 5 6 7 8 9 10 11 12 13 14...
Truncated

Test 4

Group: 1

Verdict: ACCEPTED

input
100 2
100 92 62 88 12 7 43 31 19 72 ...

correct output
YES
2876
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

user output
YES
2438
1 2 3 4 5 6 7 8 9 10 11 12 13 ...
Truncated

Test 5

Group: 1

Verdict: ACCEPTED

input
100 2
100 99 98 97 96 95 94 93 92 91...

correct output
YES
5248
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

user output
YES
4950
1 2 3 4 5 6 7 8 9 10 11 12 13 ...
Truncated

Test 6

Group: 2

Verdict: ACCEPTED

input
5 3
1 2 3 4 5

correct output
YES
0

user output
YES
0

Test 7

Group: 2

Verdict: ACCEPTED

input
5 3
3 5 4 1 2

correct output
NO

user output
NO

Test 8

Group: 2

Verdict: ACCEPTED

input
5 3
5 2 1 4 3

correct output
YES
8
1 2 1 3 1 2 3 1

user output
YES
2
1 3 

Test 9

Group: 2

Verdict: ACCEPTED

input
20 3
19 14 1 18 3 4 11 20 13 6 17 8...

correct output
YES
52
8 10 12 14 16 18 1 3 5 7 9 11 ...

user output
YES
42
8 10 12 14 16 18 1 3 5 7 9 11 ...
Truncated

Test 10

Group: 2

Verdict: ACCEPTED

input
20 3
9 6 13 18 5 10 3 2 7 20 1 4 19...

correct output
YES
50
10 12 14 16 18 13 15 17 4 6 8 ...

user output
YES
34
10 12 14 16 18 13 15 17 4 6 8 ...

Test 11

Group: 2

Verdict: ACCEPTED

input
500 3
53 52 21 76 25 142 5 4 83 176 ...

correct output
YES
15194
334 336 338 340 342 344 346 34...

user output
YES
15174
334 336 338 340 342 344 346 34...
Truncated

Test 12

Group: 2

Verdict: ACCEPTED

input
500 3
51 44 147 172 1 28 27 82 233 1...

correct output
YES
15565
366 368 370 372 374 376 378 38...

user output
YES
15543
366 368 370 372 374 376 378 38...
Truncated

Test 13

Group: 2

Verdict: ACCEPTED

input
500 3
75 46 179 62 221 14 67 154 89 ...

correct output
YES
15920
454 456 458 460 462 464 466 46...

user output
YES
15902
454 456 458 460 462 464 466 46...
Truncated

Test 14

Group: 2

Verdict: ACCEPTED

input
500 3
161 54 285 12 71 142 111 94 97...

correct output
YES
15931
408 410 412 414 416 418 420 42...

user output
YES
15907
408 410 412 414 416 418 420 42...
Truncated

Test 15

Group: 2

Verdict: ACCEPTED

input
500 3
122 260 455 113 315 276 433 43...

correct output
NO

user output
NO

Test 16

Group: 2

Verdict: ACCEPTED

input
500 3
499 500 497 498 495 496 493 49...

correct output
YES
62264
2 4 6 8 10 12 14 16 18 20 22 2...

user output
YES
62250
2 4 6 8 10 12 14 16 18 20 22 2...
Truncated

Test 17

Group: 3

Verdict: ACCEPTED

input
5 4
1 2 3 4 5

correct output
YES
0

user output
YES
0

Test 18

Group: 3

Verdict: ACCEPTED

input
5 4
5 1 2 3 4

correct output
YES
4
1 2 1 2

user output
YES
4
1 2 1 2 

Test 19

Group: 3

Verdict: ACCEPTED

input
500 4
58 14 107 124 4 113 24 290 56 ...

correct output
YES
15698
389 392 395 398 401 404 407 41...

user output
YES
14819
389 392 395 398 401 404 407 41...
Truncated

Test 20

Group: 3

Verdict: ACCEPTED

input
500 4
113 187 278 242 23 67 48 298 3...

correct output
YES
15004
480 481 480 482 485 488 491 49...

user output
YES
14076
484 485 484 485 488 491 494 49...
Truncated

Test 21

Group: 3

Verdict: ACCEPTED

input
500 4
5 233 199 35 213 354 11 134 30...

correct output
YES
16770
458 461 464 467 470 473 476 47...

user output
YES
15723
458 461 464 467 470 473 476 47...
Truncated

Test 22

Group: 3

Verdict: ACCEPTED

input
500 4
169 47 21 137 57 138 360 147 4...

correct output
YES
15889
497 371 372 371 373 376 379 38...

user output
YES
14957
497 375 376 375 376 379 382 38...
Truncated

Test 23

Group: 3

Verdict: ACCEPTED

input
500 4
493 409 291 313 156 443 496 40...

correct output
YES
22886
480 481 480 482 485 488 491 49...

user output
YES
22009
484 485 484 485 488 491 494 49...
Truncated

Test 24

Group: 3

Verdict: ACCEPTED

input
500 4
137 99 100 226 326 298 140 340...

correct output
NO

user output
NO

Test 25

Group: 3

Verdict: ACCEPTED

input
500 4
500 499 498 497 496 495 494 49...

correct output
YES
41458
1 2 1 2 5 8 11 14 17 20 23 26 ...

user output
YES
41420
1 2 1 2 5 8 11 14 17 20 23 26 ...
Truncated

Test 26

Group: 4

Verdict: ACCEPTED

input
5 5
1 2 3 4 5

correct output
YES
0

user output
YES
0

Test 27

Group: 4

Verdict: ACCEPTED

input
5 5
5 4 3 2 1

correct output
YES
1
1

user output
YES
1

Test 28

Group: 4

Verdict: ACCEPTED

input
500 5
145 26 285 154 147 314 141 40 ...

correct output
YES
13786
216 220 224 228 232 236 240 24...

user output
YES
13274
216 220 224 228 232 236 240 24...
Truncated

Test 29

Group: 4

Verdict: ACCEPTED

input
500 5
137 22 399 292 249 6 51 224 42...

correct output
YES
13465
456 460 464 468 472 476 480 48...

user output
YES
13097
456 460 464 468 472 476 480 48...
Truncated

Test 30

Group: 4

Verdict: ACCEPTED

input
500 5
153 52 85 100 329 60 433 468 4...

correct output
YES
13642
377 378 377 380 384 388 392 39...

user output
YES
13094
382 383 384 388 392 396 400 40...
Truncated

Test 31

Group: 4

Verdict: ACCEPTED

input
500 5
267 326 95 108 189 32 291 366 ...

correct output
YES
14639
213 214 213 216 220 224 228 23...

user output
YES
14073
218 219 220 224 228 232 236 24...
Truncated

Test 32

Group: 4

Verdict: ACCEPTED

input
500 5
15 450 272 80 321 101 247 438 ...

correct output
NO

user output
NO

Test 33

Group: 4

Verdict: ACCEPTED

input
499 5
497 498 499 496 495 494 493 49...

correct output
YES
30886
3 7 11 15 19 23 27 31 35 39 43...

user output
YES
30876
3 7 11 15 19 23 27 31 35 39 43...
Truncated

Test 34

Group: 4

Verdict: ACCEPTED

input
500 5
499 500 497 498 495 496 493 49...

correct output
YES
30919
1 4 8 12 16 20 24 28 32 36 40 ...

user output
YES
31377
2 3 4 8 12 16 20 24 28 32 36 4...
Truncated