2013ACM/ICPC亚洲区南京站现场赛 Wall Painting

题意:
给一个长度为 n n n的序列,求所有数据 1... n 1...n 1...n任意组合异或累加的答案,不考虑顺序
对于 1 1 1,我们只需要求序列的和,对于 2 2 2我们可以找所有两个异或的答案累加,不考虑顺序。

思路:
将每个数处理为2进制串,然后依次枚举二进制串上的每一位,然后利用组合数学求所有异或答案为1的可能,然后乘上 k m s ( 2 , j ) , j kms(2,j),j kms(2,j)j代表二进制串上的位数

c++不知道为什么 T L E TLE TLE,g++可过

参考代码:

/*
 * @Author: vain
 * @Date: 2020-08-26 11:58:46
 * @LastEditTime: 2020-09-04 21:37:48
 * @LastEditors: sueRimn
 * @Description: In User Settings Edit
 * @FilePath: \main\demo.cpp
 */
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
using namespace std;
typedef long long ll;
//#define ll long long
typedef unsigned long long ull;
const ll N = 2e3 + 20;
const ll maxn = 1e5 + 20;
const ll mod = 1e6 + 3;
ll head[maxn], stac[maxn];
ll a[maxn], b[N], c[maxn], cnt;
//typedef pair p;
//priority_queue, greater

> m; ll sum[35][N]; ll max(ll a, ll b) { return a > b ? a : b; } ll min(ll a, ll b) { return a < b ? a : b; } ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; } ll lcm(ll a, ll b) { return a * b / gcd(a, b); } void swap(ll &x, ll &y) { x ^= y, y ^= x, x ^= y; } map<string, ll> pll, che, mp; ll f[N][35], dp[35][2]; int lowbit(int x) { return (x) & (-x); } vector<string> fc; ull h[maxn], p[maxn]; const ull base = 13331; char s1[maxn]; ll ksm(ll a, ll b) { ll res = 1; while (b) { if (b & 1) res = res * a % mod; b >>= 1; a = a * a % mod; } return res % mod; } ll fac[maxn], inv[maxn]; void init() { fac[0] = inv[0] = 1; for (int i = 1; i < N; i++) { fac[i] = (fac[i - 1] * i) % mod; inv[i] = ksm(fac[i], mod - 2); } } ll C(ll n, ll m) { if (n < 0 || m < 0 || m > n) return 0; return (fac[n] * inv[m] % mod) * inv[n - m] % mod; } void solv(ll x, ll k) { for (int i = 31; i >= 0; i--) f[k][i] = (x >> i) & 1; } ll get(int x, int j) { ll ans = 0; for (int i = 1; i <= j; i += 2) { ans = (ans + C(dp[x][1], i) * C(dp[x][0], j - i)) % mod; } return ans; } int main() { ios::sync_with_stdio(false); cin.tie(0), cout.tie(0); srand(time(NULL)); ll n, m, ans, t, x; init(); while (cin >> n) { for (int i = 0; i < 33; i++) dp[i][0] = dp[i][1] = 0; for (int i = 0; i < n; i++) { cin >> x, solv(x, i); } for (int i = 0; i < 32; i++) { for (int j = 0; j < n; j++) { dp[i][f[j][i]]++; } } for (int i = 0; i < 32; i++) { for (int j = 1; j <= n; j++) { sum[i][j] = get(i, j); } } for (int i = 1; i <= n; i++) { ll ans = 0; for (int j = 0; j < 32; j++) { ans = (ans + ksm(2, j) * sum[j][i]) % mod; } if (i != n) cout << ans << ' '; else cout << ans << endl; } } }

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