[Offer收割]编程练习赛58

最大的K-偏差排列

分类讨论

#include <bits/stdc++.h>
using namespace std;
int p[111];

int main() {
    int N, K;
    scanf("%d %d", &N, &K);
    for (int i = 1; i <= N; ++i) p[i] = i;
    for (int i = 1; i + K + K - 1 <= N; i += K + K) {
        for (int j = i; j < i + K; ++j) swap(p[j], p[j + K]);
    }
    int t = N / (K + K) * (K + K);
    if (N - t > K) {
        for(int i = t + 1; i + K <= N; ++i) swap(p[i], p[i+K]);
        for(int i = N - K + 1, j = t + K; i < j; ++i, --j) swap(p[i], p[j]);
    } else {
        for (int i = t + 1, j = N; i < j; ++i, --j) swap(p[i], p[j]);
    }
    for (int i = 1; i <= N; ++i) printf("%d%c", p[i], i == N ? '
' : ' ');
    return 0;
}

孤独的字符

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
typedef long long LL;
vector<int> p[26];
char T[maxn];

int main() {
    scanf("%s", T + 1);
    int lt = strlen(T + 1);
    for (int i = 0; i < 26; ++i) p[i].push_back(0);
    for (int i = 1; i <= lt; ++i) p[T[i] - 'a'].push_back(i);
    for (int i = 0; i < 26; ++i) p[i].push_back(lt + 1);
    LL ans = 0;
    for (int i = 0; i < 26; ++i) {
        for (int j = 1; j < p[i].size() - 1; ++j) ans += (LL) (p[i][j] - p[i][j - 1]) * (p[i][j + 1] - p[i][j]);
    }
    printf("%lld
", ans);
    return 0;
}

秋天来了

好像只有我线段树建图缩点了…好像离线就可以直接线段树了…

UPD：出题人说直接扫一遍就好了QAQ

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
const int maxn = 1e5 + 10;
int id[maxn], MP;

int deg[maxn<<2], ans[maxn<<2];
vector<pii> G[maxn<<2], GG[maxn<<2];
void build(int p, int tl, int tr) {
    MP = max(MP, p);
    if (tl < tr) {
        int mid = (tl + tr) >> 1;
        build(p << 1, tl, mid);
        G[p].push_back(pii(p << 1, 0));
        build(p << 1 | 1, mid + 1, tr);
        G[p].push_back(pii(p << 1 | 1, 0));
    } else id[tl] = p;
}
void add(int p, int tl, int tr, int l, int r, int x) {
    if (l > tr || r < tl) return;
    if (l <= tl && tr <= r) {
        G[x].push_back(pii(p, 1));
        return;
    }
    int mid = (tl + tr) >> 1;
    add(p << 1, tl, mid, l, r, x);
    add(p << 1 | 1, mid + 1, tr, l, r, x);
}

// BCC
stack<int> S;
int dfs_clock, dfn[maxn<<2], low[maxn<<2];
int bcc_cnt, bccno[maxn<<2];
void dfs(int u)
{
    dfn[u] = low[u] = ++dfs_clock;
    S.push(u);
    for(int i = 0; i < G[u].size(); i++)
    {
        int v = G[u][i].first;
        if(!dfn[v])
        {
            dfs(v);
            low[u] = min(low[u], low[v]);
        }
        else if(!bccno[v]) low[u] = min(low[u], dfn[v]);
    }

    if(low[u] == dfn[u])
    {
        bcc_cnt++;
        while(1)
        {
            int x = S.top(); S.pop();
            bccno[x] = bcc_cnt;
            if(x == u) break;
        }
    }
}

void find_bcc(int n)
{
    memset(dfn, 0, sizeof(dfn));
    memset(bccno, 0, sizeof(bccno));
    dfs_clock = bcc_cnt = 0;
    for(int i = 1; i <= n; i++) if(!dfn[i]) dfs(i);
}

queue<int> q;
int main() {
    int N, I, H, R;
    scanf("%d %d %d %d", &N, &I, &H, &R);
    build(1, 1, N);
    for(int i = 1; i <= R; ++i){
        int A, B;
        scanf("%d %d", &A, &B);
        G[id[B]].push_back(pii(id[A], 0));
        if(min(A, B) < max(A, B) - 1) add(1, 1, N, min(A, B) + 1, max(A, B) - 1, id[A]);
    }
    find_bcc(MP);
    for(int i = 1; i <= MP; ++i){
        for(int j = 0; j < G[i].size(); ++j){
            int to = G[i][j].first, d = G[i][j].second;
            if(bccno[i] != bccno[to]){
                deg[bccno[to]]++;
                GG[bccno[i]].push_back(pii(bccno[to], d));
            }
        }
    }
    for(int i = 1; i <= bcc_cnt; ++i) {
        ans[i] = H;
        if(deg[i] == 0) q.push(i);
    }
    while (!q.empty()){
        int x = q.front();
        q.pop();
        for(int i = 0; i < GG[x].size(); ++i){
            int to = GG[x][i].first, d = GG[x][i].second;
            deg[to]--;
            ans[to] = min(ans[to], ans[x] - d);
            if(deg[to] == 0) q.push(to);
        }
    }
    for(int i = 1; i <= N; ++i) printf("%d
", ans[bccno[id[i]]]);
    return 0;
}

Nim森林

又爆LL也是服气…int128真叼

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
typedef long long LL;
LL a[maxn], W[maxn], b[66];
int id[maxn];

bool cmp(int i, int j) {
    return W[i] > W[j];
}

void print(__int128 x){
    string s = "";
    while(x) s += x % 10 + '0', x /= 10;
    reverse(s.begin(), s.end());
    if(s == "") s = "0";
    cout << s << endl;
    return;
}

int main(){
    int N, one = 0;
    scanf("%d", &N);
    N--;
    __int128 tot = 0, sum = 0;
    for(int i = 1; i <= N; ++i){
        LL u, v;
        scanf("%lld %lld %lld %lld", &u, &v, a + i, W + i);
        W[i] ^= u ^ v;
        tot += W[i];
        id[i] = i;
        if(a[i] == 1) one++;
    }
    if(one == N) {
        puts("No");
        return 0;
    }
    sort(id + 1, id + 1 + N, cmp);
    for(int i = 1; i <= N; ++i){
        int x = id[i];
        if(a[x] == 1) continue;
        for(int j = 0; j <= 60; ++j){
            if(a[x] & (1LL << j)){
                if(b[j]) a[x] ^= b[j];
                else {
                    b[j] = a[x];
                    sum += W[x];
                    break;
                }
            }
        }
    }
    print(tot - sum);
    return 0;
}