Submission #256102

#	Time	Username	Problem	Language	Result	Execution time	Memory
256102		karma	Red-blue table (IZhO19_stones)	C++14	100 / 100	44 ms	2296 KiB

stones

#include <bits/stdc++.h>
#define pb          emplace_back
#define ll          long long
#define fi          first
#define se          second
#define mp          make_pair
//#define int         int64_t

using namespace std;

const int N = int(1e3) + 7;
const int inf = 1e9 + 1;
typedef pair<ll, ll> pii;

int n, m, nr, nc, r, c, res;
void solve() {
    cin >> n >> m;
    res = m, r = 0, c = m;
    nr = m / 2 + 1, nc = n / 2 + 1;
    for(int l, h, mid, i = 1; i <= n; ++i) {
        l = 0, h = m;
        while(l <= h) {
            mid = l + h >> 1;
            int x = min(mid, m - nr);
            int tmp = x * (n - nc);
            if(nr - m + mid <= 0) l = mid + 1;
            else if(tmp / (nr - m + mid) + (n - nc) >= i) l = mid + 1;
            else h = mid - 1;
        }
        if(i + h > res) res = i + h, r = i, c = h;
    }
    cout << res << '\n';
    vector<vector<char>> ans(n, vector<char>(m, '-'));
    int x = 0;
    for(int i = 0; i < r; ++i) {
        int tmp = nr;
        for(int j = m - 1; tmp > 0 && j >= c; --j, --tmp)
            ans[i][j] = '+';
        while(tmp--) {
            ans[i][x] = '+';
            x++;
            if(x >= c) x = 0;
        }
    }
    for(int i = 0; i < n; ++i) {
        for(int j = 0; j < m; ++j) cout << ans[i][j];
        cout << '\n';
    }
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    #define Task        "test"
    if(fopen(Task".inp", "r")) {
        freopen(Task".inp", "r", stdin);
        freopen(Task".out", "w", stdout);
    }
    int T; cin >> T;
    while(T --) solve();
}

Compilation message (stderr)

stones.cpp: In function 'void solve()':
stones.cpp:23:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
             mid = l + h >> 1;
                   ~~^~~
stones.cpp: In function 'int32_t main()':
stones.cpp:56:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".inp", "r", stdin);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
stones.cpp:57:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".out", "w", stdout);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 17 / 17
• Subtask 2: 10 / 10
• Subtask 3: 16 / 16
• Subtask 4: 11 / 11
• Subtask 5: 15 / 15
• Subtask 6: 31 / 31