Submission #699092

#	Time	Username	Problem	Language	Result	Execution time	Memory
699092		DennisTran	Lasers (NOI19_lasers)	C++17	10 / 100	31 ms	7056 KiB

lasers

#pragma GCC optimize("O2")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FOD(i, a, b) for (int i = (a); i >= (b); i--)
#define REP(i, n) for (int i = 0; i < (n); i++)
#define ALL(x) (x).begin(), (x).end()
#define TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
#define ii pair <int, int>
#define fi first
#define se second
using namespace std;

const int MAXN = 5e5 + 5;

int L, R, a[MAXN], sum[MAXN];
vector <ii> ans;
void solve(void) {
    cin >> L >> R;
    FOR(i, 1, R) {
        int n; cin >> n;
        FOR(i, 1, n) cin >> a[i], sum[i] = sum[i - 1] + a[i];
        vector <ii> lines;
        FOR(i, 0, n) {
            int l = sum[i] + 1;
            int r = L - sum[n] + sum[i];
            if (r >= l) lines.emplace_back(l, r);
        }
        vector <ii> new_lines;
        new_lines.emplace_back(0, 0);
        for (auto x : lines) 
            if (x.fi <= new_lines.back().se) 
                new_lines.back().se = x.se;
            else new_lines.emplace_back(x);
        new_lines.emplace_back(L + 1, L + 1);
        REP(i, (int) new_lines.size() - 1) {
            int l = new_lines[i].se + 1, r = new_lines[i + 1].fi - 1;
            if (r >= l && l > 0) ans.emplace_back(l, r);
        }
    }
    vector <ii> new_ans;
    sort(ALL(ans));
    for (auto x : ans) 
        if (new_ans.size() && x.fi <= new_ans.back().se)
            new_ans.back().se = x.se;
        else new_ans.emplace_back(x);
    int ans = 0;
    for (auto x : new_ans) ans += x.se - x.fi + 1;
    cout << ans;
}

signed main(void) {
    ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
    file("LASERS");
    //int T; cin >> T; while (T--) 
    solve();
    cerr << "Time elapsed: " << TIME << " s.\n";
    return (0 ^ 0);
}

Compilation message (stderr)

lasers.cpp: In function 'int main()':
lasers.cpp:9:58: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 | #define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
lasers.cpp:55:5: note: in expansion of macro 'file'
   55 |     file("LASERS");
      |     ^~~~
lasers.cpp:9:91: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 | #define file(name)  if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                    ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
lasers.cpp:55:5: note: in expansion of macro 'file'
   55 |     file("LASERS");
      |     ^~~~

• Subtask 1: 10 / 10
• Subtask 2: 0 / 14
• Subtask 3: 0 / 20
• Subtask 4: 0 / 21
• Subtask 5: 0 / 22
• Subtask 6: 0 / 13