109 lines
2 KiB
C++
109 lines
2 KiB
C++
#include <bits/stdc++.h> // {{{
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#include <version>
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#ifdef __cpp_lib_ranges_enumerate
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#include <ranges>
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namespace rv = std::views;
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namespace rs = std::ranges;
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#endif
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// https://codeforces.com/blog/entry/96344
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#pragma GCC optimize("O2,unroll-loops")
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#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
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using namespace std;
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using i16 = int16_t;
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using u16 = uint16_t;
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using i32 = int32_t;
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using u32 = uint32_t;
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using i64 = int64_t;
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using u64 = uint64_t;
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using f64 = double;
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using f128 = long double;
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#if __cplusplus >= 202002L
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template <typename T> constexpr T MIN = std::numeric_limits<T>::min();
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template <typename T> constexpr T MAX = std::numeric_limits<T>::max();
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template <typename T> [[nodiscard]] static T sc(auto &&x) {
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return static_cast<T>(x);
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}
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template <typename T> [[nodiscard]] static T sz(auto &&x) {
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return static_cast<T>(x.size());
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}
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#endif
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static void NO() { std::cout << "NO\n"; }
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static void YES() { std::cout << "YES\n"; }
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template <typename T> using vec = std::vector<T>;
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#define all(x) (x).begin(), (x).end()
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#define rall(x) (x).rbegin(), (x).rend()
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#define ff first
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#define ss second
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#ifdef LOCAL
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#define db(...) std::print(__VA_ARGS__)
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#define dbln(...) std::println(__VA_ARGS__)
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#else
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#define db(...)
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#define dbln(...)
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#endif
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// }}}
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void solve() {
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u32 n, m;
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cin >> n >> m;
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u32 a, b;
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u16 side = 0;
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u32 t = 0;
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u32 ans = 0;
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for (u32 i = 0; i < n; ++i) {
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cin >> a >> b;
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// at time a, must be at side b; was on side side @ time t
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u32 diff = a - t;
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ans += diff;
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if (diff & 1 && b == side || !(diff & 1) && b != side) {
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--ans;
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}
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t = a;
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side = b;
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}
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ans += m - t;
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println("{}", ans);
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}
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int main() { // {{{
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std::cin.exceptions(std::cin.failbit);
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#ifdef LOCAL
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std::cerr.rdbuf(std::cout.rdbuf());
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std::cout.setf(std::ios::unitbuf);
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std::cerr.setf(std::ios::unitbuf);
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#else
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std::cin.tie(nullptr)->sync_with_stdio(false);
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#endif
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u32 tc = 1;
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std::cin >> tc;
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for (u32 t = 0; t < tc; ++t) {
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solve();
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}
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return 0;
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}
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// }}}
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