Submission #146180

#	Time	Username	Problem	Language	Result	Execution time	Memory
146180		imeimi2000	Intergalactic ship (IZhO19_xorsum)	C++17	100 / 100	982 ms	6996 KiB

xorsum

#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;
typedef long long llong;

const int mod = 1e9 + 7;

int n, q;
int A[1001];
struct _qs {
    int l, r, x;
    void scan() {
        cin >> l >> r >> x;
    }
} qs[100000];

int P2[100001];
int cnt[1001][1001];
int S[7][1002];
int solve(int a, int b) {
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= i; ++j) {
            cnt[j][i] = 0;
        }
    }
    for (int it = 0; it < q; ++it) {
        _qs i = qs[it];
        bool b1 = (i.x >> a) & 1, b2 = (i.x >> b) & 1;
        if (!b1 || !b2) continue;
        ++cnt[i.l][i.r];
    }
    for (int l = 1; l <= n; ++l) {
        for (int r = n - 1; l <= r; --r) {
            cnt[l][r] = (cnt[l][r] + cnt[l][r + 1]) % mod;
        }
    }
    for (int l = 2; l <= n; ++l) {
        for (int r = n; l <= r; --r) {
            cnt[l][r] = (cnt[l][r] + cnt[l - 1][r]) % mod;
        }
    }
    llong ret = 0;
    for (int l = 1; l <= n; ++l) {
        for (int r = 1; r <= n; ++r) {
            if (l > r) cnt[l][r] = cnt[r][l];
            llong C[2][2] = {};
            C[1][1] = cnt[l][r];
            C[1][0] = S[a][l] - C[1][1];
            C[0][1] = S[b][r] - C[1][1];
            C[0][0] = q - C[0][1] - C[1][0] - C[1][1];
            llong sum = 0;
            int x = (A[l] >> a) & 1; x ^= 1;
            int y = (A[r] >> b) & 1; y ^= 1;
            int v = q;
            for (int i = 0; i < 2; ++i) {
                for (int j = 0; j < 2; ++j) {
                    if (i == 0 && j == 0) continue;
                    if (C[i][j] > 0) --v;
                }
            }
            v = P2[v];
            for (int i = 0; i < 2; ++i) {
                int k = i ^ x;
                int j = k ^ y;
                if (C[1][0] < i) continue;
                if (C[0][1] < j) continue;
                if (C[1][1] < k) continue;
                sum += v;
            }
            v = (n - max(l, r) + 1) * min(l, r);
            ret += (sum << a + b) % mod * v;
            ret %= mod;
        }
    }
    if (a != b) ret = (ret << 1) % mod;
    return ret;
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> A[i];
    }
    cin >> q;
    P2[0] = 1;
    for (int i = 0; i < q; ++i) {
        qs[i].scan();
        P2[i + 1] = (P2[i] << 1) % mod;
        for (int j = 0; j < 7; ++j) {
            if ((qs[i].x >> j) & 1) {
                ++S[j][qs[i].l];
                --S[j][qs[i].r + 1];
            }
        }
    }
    for (int j = 0; j < 7; ++j) {
        for (int i = 1; i <= n; ++i) {
            S[j][i] += S[j][i - 1];
        }
    }
    llong ans = 0;
    for (int i = 0; i < 7; ++i) {
        for (int j = 0; j <= i; ++j) {
            ans += solve(j, i);
        }
    }
    printf("%lld\n", ans % mod);
    return 0;
}

Compilation message (stderr)

xorsum.cpp: In function 'int solve(int, int)':
xorsum.cpp:73:30: warning: suggest parentheses around '+' inside '<<' [-Wparentheses]
             ret += (sum << a + b) % mod * v;
                            ~~^~~

• Subtask 1: 4 / 4
• Subtask 2: 5 / 5
• Subtask 3: 6 / 6
• Subtask 4: 9 / 9
• Subtask 5: 8 / 8
• Subtask 6: 11 / 11
• Subtask 7: 19 / 19
• Subtask 8: 30 / 30
• Subtask 9: 8 / 8