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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#373234#7730. Convex CheckerdodolaCompile Error//C++143.4kb2024-04-01 11:50:002024-04-01 11:50:02

Judging History

你现在查看的是最新测评结果

  • [2024-07-04 19:27:17]
  • hack成功,自动添加数据
  • (/hack/727)
  • [2024-07-04 19:17:30]
  • hack成功,自动添加数据
  • (/hack/726)
  • [2024-04-01 11:50:02]
  • 评测
  • [2024-04-01 11:50:00]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
typedef unsigned long long ull;
typedef long long ll;
typedef double ld;
const ld eps = 1e-18;
const ld pi = acos(-1.0);
/*
符合洛谷题目格式的代码
*/

struct point {
    ld x, y;
    point operator+(const point& p)const {
        return { x + p.x,y + p.y };
    }
    point operator-(const point& p)const {
        return { x - p.x,y - p.y };
    }
    bool operator==(const point& p)const {
        return p.x == x && p.y == y;
    }
    point rotate(ld t)const {
        return { x * cos(t) - y * sin(t), x * sin(t) + y * cos(t) };
    }
    point rot90()const {
        return { -y,x };
    }
};

struct line {
    point s, t;
};

int sgn(ld x) {
    if (fabs(x) < eps) return 0;
    return x < 0 ? -1 : 1;
}
ld sqr(ld x) {
    return x * x;
}
ld dis(const point& a, const point& b) {
    return sqrt(sqr(a.x - b.x) + sqr(a.y - b.y));
}

ld dot(const point& a, const point& b) {
    return a.x * b.x + a.y * b.y;
}
ld det(const point& a, const point& b) {
    return a.x * b.y - a.y * b.x;
}
vector<point>Andrew(vector<point>& p) {
    sort(p.begin(), p.end(), [](const point& a, const point& b) {
        return a.x == b.x ? a.y < b.y : a.x < b.x;
        });
    vector<point> res;
    for (int i = 0; i < p.size(); i++) {    // 下凸壳
        while (res.size() > 1
            && det(res.back() - res[res.size() - 2], p[i] - res[res.size() - 2]) <= 0)
            res.pop_back();
        res.push_back(p[i]);
    }
    int k = res.size();
    for (int i = p.size() - 2; i >= 0; i--) {   // 上凸壳
        while (res.size() > k
            && det(res.back() - res[res.size() - 2], p[i] - res[res.size() - 2]) <= 0)
            res.pop_back();
        res.push_back(p[i]);
    }
    res.pop_back(); // 删除重复的点,即首尾相同
    return res;
}

bool turn_left(const point& a, const point& b, const point& c) {
    return sgn(det(b - a, c - a)) > 0;
}

vector<point> Graham(vector<point>& p) {
    point base = *min_element(p.begin(), p.end(), [](const point& a, const point& b) {
        return a.y == b.y ? a.x < b.x : a.y < b.y;
        });
    sort(p.begin(), p.end(), [&](const point& u, const point& v) {
        int s = sgn(det(u - base, v - base));
        if (s)return s > 0;
        return sgn(dis(u, base) - dis(v, base)) < 0;
        });
    vector<point>res;
    for (auto i : p) {
        while (res.size() > 1
            && !turn_left(res[res.size() - 2], res.back(), i))
            res.pop_back();
        res.push_back(i);
    }
    return res;
}

// 求凸包的周长
ld convex_perimeter(vector<point>& p) {
    ld res = 0;
    for (int i = 0; i < p.size(); i++)
        res += dis(p[i], p[(i + 1) % p.size()]);
    return res;
}

bool convex_checker(vector<point>& p) {
    vector<point> res = Andrew(p);
    if (res.size() != p.size())return false;
    while (p.size() && p.front() != res.front()) {
        res.push_back(res.front());
        res.erase(res.begin());
    }
    for (int i = 0; i < p.size(); i++) {
        if (p[i] != (res[i]))return false;
    }
    return true;
}

void solve() {
    ll n;cin >> n;
    vector<point> p(n);
    for (ll i = 0;i < n;i++) {
        cin >> p[i].x >> p[i].y;
    }
    if (convex_checker(p)) {
        cout << "Yes" << endl;
    }
    else {
        cout << "No" << endl;
    }
}

int main() {
    solve();

    return 0;
}

Details

answer.code: In function ‘bool convex_checker(std::vector<point>&)’:
answer.code:108:34: error: no match for ‘operator!=’ (operand types are ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’} and ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’})
  108 |     while (p.size() && p.front() != res.front()) {
      |                        ~~~~~~~~~ ^~ ~~~~~~~~~~~
      |                               |              |
      |                               |              __gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type {aka point}
      |                               __gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type {aka point}
In file included from /usr/include/c++/13/regex:68,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:181,
                 from answer.code:1:
/usr/include/c++/13/bits/regex.h:1132:5: note: candidate: ‘template<class _BiIter> bool std::__cxx11::operator!=(const sub_match<_BiIter>&, const sub_match<_BiIter>&)’
 1132 |     operator!=(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/13/bits/regex.h:1132:5: note:   template argument deduction/substitution failed:
answer.code:108:47: note:   ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
  108 |     while (p.size() && p.front() != res.front()) {
      |                                               ^
/usr/include/c++/13/bits/regex.h:1212:5: note: candidate: ‘template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator!=(__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const sub_match<_BiIter>&)’
 1212 |     operator!=(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/13/bits/regex.h:1212:5: note:   template argument deduction/substitution failed:
answer.code:108:47: note:   ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’} is not derived from ‘std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>’
  108 |     while (p.size() && p.front() != res.front()) {
      |                                               ^
/usr/include/c++/13/bits/regex.h:1305:5: note: candidate: ‘template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator!=(const sub_match<_BiIter>&, __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)’
 1305 |     operator!=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/13/bits/regex.h:1305:5: note:   template argument deduction/substitution failed:
answer.code:108:47: note:   ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
  108 |     while (p.size() && p.front() != res.front()) {
      |                                               ^
/usr/include/c++/13/bits/regex.h:1379:5: note: candidate: ‘template<class _Bi_iter> bool std::__cxx11::operator!=(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)’
 1379 |     operator!=(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/13/bits/regex.h:1379:5: note:   template argument deduction/substitution failed:
answer.code:108:47: note:   ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
  108 |     while (p.size() && p.front() != res.front()) {
      |                                               ^
/usr/include/c++/13/bits/regex.h:1473:5: note: candidate: ‘template<class _Bi_iter> bool std::__cxx11::operator!=(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)’
 1473 |     operator!=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/13/bits/regex.h:1473:5: note:   template argument deduction/substitution failed:
answer.code:108:47: note:   ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
  108 |     while (p.size() && p.front() != res.front()) {
      |                                               ^
/usr/include/c++/13/bits/regex.h:1547:5: note: candidate: ‘template<class _Bi_iter> bool std::__cxx11::operator!=(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)’
 1547 |     operator!=(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/13/bits/regex.h:1547:5: note:   template argument deduction/substitution failed:
answer.code:108:47: note:   ‘__gnu_cxx::__alloc_traits<std::allocator<point>, point>::value_type’ {aka ‘point’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
  108 |     while (p.size() && p.front() != res.front()) ...