2018-2019 ICPC Southwestern European Regional Programming Contest (SWERC 2018)

7题，一般般。F没搞出来很可惜。

自己这场题还是充当翻译机的角色……中间发现D和H很可写，马上就把队友赶下来了(

---

A：

solver：lzh

#include<bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
typedef long long ll;
#define ff first
#define ss second

int a[1000010];
int main() {
    int n, k; scanf("%d%d", &n, &k);
    for (int i = 1; i <= n; i++)a[i] = 1;
    int ans = 0, cur = 0;
    while (k--) {
        int m, cnt = cur; scanf("%d", &m);
        for (int i = 1; i * m <= n; i++) {
            if (!a[i * m])cnt--;
            else cnt++;
            a[i * m] ^= 1;
        }
        ans = max(ans, cnt);
        //cout<<cnt<<endl;
        cur = cnt;
    }
    printf("%d\n", ans);
}

B：

solver：lzh

#include<bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
typedef long long ll;
#define ff first
#define ss second

int dl[20][100010], dr[20][100010];
int query(int d[][100010], int l, int r, int maxx) {
    int t = log2(r - l + 1);
    if (maxx)return max(d[t][l], d[t][r - (1 << t) + 1]);
    return min(d[t][l], d[t][r - (1 << t) + 1]);
}
void init(int d[][100010], int a[], int len, int maxx) {
    for (int i = 0; i < len; i++)d[0][i] = a[i];
    int t = 1;
    for (int i = 1; t <= len; i++) {
        for (int j = 0; j + t < len; j++)
            if (maxx)d[i][j] = max(d[i - 1][j], d[i - 1][j + t]);
            else d[i][j] = min(d[i - 1][j], d[i - 1][j + t]);
        t <<= 1;
    }
}

int L[100010], R[100010];
int main() {
    int n; scanf("%d", &n);
    for (int i = 0; i < n; i++)scanf("%d%d", &L[i], &R[i]);
    init(dl, L, n, 1);
    init(dr, R, n, 0);

    int ans = 1;
    for (int i = 1; i <= n; i++) {
        int l = ans, r = n - i + 1;
        while (l <= r) {
            int mid = l + r >> 1;
            //cout<<i<<" "<<mid<<" "<<query(dl,i-1,i+mid-2,1)<<" "<<query(dr,i-1,i+mid-2,0)<<"\n";
            if (query(dr, i - 1, i + mid - 2, 0) - query(dl, i - 1, i + mid - 2, 1) + 1 >= mid) {
                ans = max(ans, mid); l = mid + 1;
            } else r = mid - 1;
        }
    }
    printf("%d\n", ans);
}

C：

完全没看的防AK

D：

solver：czq

/* basic header */
#include <bits/stdc++.h>
/* define */
#define ll long long
#define dou double
#define pb emplace_back
#define mp make_pair
#define sot(a,b) sort(a+1,a+1+b)
#define rep1(i,a,b) for(int i=a;i<=b;++i)
#define rep0(i,a,b) for(int i=a;i<b;++i)
#define eps 1e-8
#define int_inf 0x3f3f3f3f
#define ll_inf 0x7f7f7f7f7f7f7f7f
#define lson (curpos<<1)
#define rson (curpos<<1|1)
/* namespace */
using namespace std;
/* header end */

const int maxn = 200010, lim = 100001;
struct Point {
    int x, y;
} p[maxn];
int n, x, y, maxx[maxn], minn[maxn], monument[maxn];

void init() {
    for (int i = 0; i < maxn; i++) {
        p[i].x = p[i].y = monument[i] = 0;
        maxx[i] = -1;
    }
    memset(minn, 0x3f, sizeof(minn));
}

int main() {
    while (~scanf("%d%d", &x, &y)) {
        init();
        scanf("%d", &n);
        for (int i = 0; i < n; i++) {
            scanf("%d%d", &p[i].x, &p[i].y);
            maxx[p[i].x] = max(maxx[p[i].x], p[i].y);
            minn[p[i].x] = min(minn[p[i].x], p[i].y);
        }
        int cnt = 0;
        for (int i = 0; i < lim; i++) {
            if (maxx[i] != -1 && minn[i] != 0x3f3f3f3f) {
                monument[cnt++] = maxx[i];
                monument[cnt++] = minn[i];
            }
        }
        sort(monument, monument + cnt);
        ll ans = x - 1, mid = monument[(cnt - 1) / 2];
        for (int i = 0; i < lim; i++)
            if (maxx[i] != -1 && minn[i] != 0x3f3f3f3f)
                ans += (ll)maxx[i] - minn[i] + abs(mid - maxx[i]) + abs(mid - minn[i]);
        printf("%lld\n", ans);
    }
    return 0;
}

E：

solver：zyh、lzh

#include <iostream>
#include <string>
using namespace std;
char str[50001];
string names[50001];
int d[50001];
int validate(int x) {
    if (x > 49) return 49;
    if (x < -50) return -50;
    return x;
}
int main() {
    int n;
    int sum = 0;
    scanf("%d", &n);
    for (int i = 0; i < n; ++i) {
        scanf("%s%d", str, &d[i]);
        d[i] *= 100;
        sum += d[i];
        names[i] = str;
    }
    int l = 10000 - sum - 49 * (n - 1);
    int r = 10000 - sum + 50 * (n - 1);
    if (r > 49) r = 49;
    if (l < -50) l = -50;
    if (l <= r) {
        for (int i = 0; i < n; ++i) {
            printf("%s %.2f %.2f\n", names[i].c_str(), max(0, d[i] + l) / 100.0, min(10000, d[i] + r) / 100.0);
        }
    } else printf("IMPOSSIBLE\n");
}

F：

没搞出来

G：

很恶心的字符串题

H：

solver：czq

/* basic header */
#include <bits/stdc++.h>
/* define */
#define ll long long
#define dou double
#define pb emplace_back
#define mp make_pair
#define sot(a,b) sort(a+1,a+1+b)
#define eps 1e-8
#define int_inf 0x3f3f3f3f
#define ll_inf 0x7f7f7f7f7f7f7f7f
#define lson (curpos<<1)
#define rson (curpos<<1|1)
/* namespace */
using namespace std;
/* header end */
using namespace std;

const int maxn = 1e5 + 10;
struct Node {
    int x, y, z, id, cnt;
    bool operator<(const Node &rhs)const {
        return x != rhs.x ? x < rhs.x : y != rhs.y ? y < rhs.y : z < rhs.z;
    }
} info[maxn], temp[maxn];
int n, m, num = 0, sum = 0, a[maxn], dis1[maxn], dis2[maxn], dis3[maxn], vis[maxn], head[maxn];
vector<pair<int, int>>g[maxn];
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>>q;

int lowbit(int x) {
    return x & -x;
}

void add(int pos, int val) {
    while (pos < maxn) a[pos] += val, pos += lowbit(pos);
}

int query(int pos) {
    int ret = 0;
    while (pos) ret += a[pos], pos -= lowbit(pos);
    return ret;
}

void dijkstra(int *dis, int st) {
    for (int i = 0; i <= n; ++i) dis[i] = int_inf;
    dis[st] = 0;
    while (q.size()) q.pop();
    q.push(mp(dis[st], st));
    while (q.size()) {
        pair<int, int> temp = q.top(); q.pop();
        if (temp.first > dis[temp.second]) continue;
        for (int i = 0; i < (int)g[temp.second].size(); ++i) {
            if (dis[temp.second] + g[temp.second][i].first < dis[g[temp.second][i].second]) {
                dis[g[temp.second][i].second] = dis[temp.second] + g[temp.second][i].first;
                q.push(mp(dis[g[temp.second][i].second], g[temp.second][i].second));
            }
        }
    }
}

void init() {
    for (int i = 0; i < maxn; i++) vis[i] = 0;
}

void cdq(int l, int r) {
    if (r - l <= 1) return;
    int mid = (r + l) >> 1;
    cdq(l, mid); cdq(mid, r);
    int lPtr = l, rPtr = mid, cnt = 0;
    while (lPtr < mid && rPtr < r) {
        if (info[lPtr].y <= info[rPtr].y) {
            add(info[lPtr].z, 1);
            temp[cnt++] = info[lPtr++];
        } else {
            int curr = query(info[rPtr].z);
            if (curr) vis[info[rPtr].id] = info[rPtr].cnt;
            temp[cnt++] = info[rPtr++];
        }
    }
    while (rPtr < r) {
        int curr = query(info[rPtr].z);
        if (curr) vis[info[rPtr].id] = info[rPtr].cnt;
        temp[cnt++] = info[rPtr++];
    }
    for (int i = l; i < lPtr; ++i) add(info[i].z, -1);
    while (lPtr < mid) temp[cnt++] = info[lPtr++];
    for (int i = 0; i < cnt; ++i) info[i + l] = temp[i];
}

int main() {
    scanf("%d%d", &n, &m); sum = n, num = 0;
    while (m--) {
        int u, v, w;
        scanf("%d%d%d", &u, &v, &w);
        g[u].pb(mp(w, v)); g[v].pb(mp(w, u));
    }
    // maintain distance
    dijkstra(dis1, 0); dijkstra(dis2, 1); dijkstra(dis3, 2);
    for (int i = 0; i < n; ++i)  info[i].x = dis1[i], info[i].y = dis2[i], info[i].z = dis3[i], head[++num] = info[i].z;
    sort(head + 1, head + 1 + num);
    // li san hua
    num = unique(head + 1, head + 1 + num) - head - 1;
    for (int i = 0; i < n; ++i) info[i].z = lower_bound(head + 1, head + 1 + num, info[i].z) - head;
    sort(info, info + n);
    int p = 1, tot = 0;
    // spj equal
    for (int i = 0; i < n; ++i) {
        if (info[i].x == info[i + 1].x && info[i].y == info[i + 1].y && info[i].z == info[i + 1].z) {
            p++; continue;
        }
        info[i].cnt = p; info[tot++] = info[i]; p = 1;
    }
    n = tot;
    for (int i = 0; i < n; ++i) info[i].id = i;
    cdq(0, n);
    for (int i = 0; i < n; ++i) sum -= vis[i];
    printf("%d\n", sum);
}

I：

solver：lzh

#include<bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
typedef long long ll;
#define ff first
#define ss second

char s[1010][1010];
int vis[1010][1010], dd[8][2] = {-1, 0, -1, -1, -1, 1, 0, 1, 0, -1, 1, 0, 1, -1, 1, 1};

int abc[3][15] = {{1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1},
    {1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1},
    {1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1}
};
int add1[20], add2[20];

int check(int x, int y, int n, int m, char cur) {
    for (int i = x; i < x + n; i++)
        for (int j = y; j < y + m; j++)
            if (s[i][j] != cur || vis[i][j])return 1;
    return 0;
}

int find(int stx, int sty, int x, int y, int cur) {
    add1[0] = 0, add1[1] = x, add1[2] = x + y;
    for (int i = 3; i < 15; i++)add1[i] = add1[i % 3];
    add2[0] = 0, add2[3] = x, add2[6] = x + y, add2[9] = 2 * x + y, add2[12] = 2 * x + 2 * y;
    for (int i = 0; i < 5; i++)
        for (int j = 1; j < 3; j++)add2[3 * i + j] = add2[3 * i + j - 1];
    //for(int i=0;i<15;i++)printf("%d ",add2[i]);printf("\n");

    for (int i = 0; i < 15; i++) {
        int addn = 0, addm = 0;
        if (i / 3 % 2 == 0)addn = x; else addn = y;
        if (i % 3 % 2 == 0)addm = x; else addm = y;

        char findchar = '.';
        if (abc[cur][i])findchar = '#';
        if (check(stx + add2[i], sty + add1[i], addn, addm, findchar)) {
            //printf("%d\n",i);
            //printf("%d %d %d %d\n",stx+add2[i],sty+add1[i],addn,addm);
            return 0;
        }
    }
    return 1;
}

int main() {
    int ansa = 0, ansb = 0, ansc = 0;
    int n, m; scanf("%d%d", &m, &n);
    for (int i = 1; i <= n; i++)scanf("%s", s[i] + 1);
    for (int i = 2; i <= n - 1; i++)
        for (int j = 2; j <= m - 1; j++)
            if (s[i][j] == '#') {
                int gg = 0;
                for (int k = 0; k < 8; k++)
                    if (s[i + dd[k][0]][j + dd[k][1]] == '#') {
                        gg++;
                        break;
                    }
                if (!gg)s[i][j] = '.';
            }

    for (int i = 2; i <= n - 1; i++)
        for (int j = 2; j <= m - 2; j++)
            if (s[i][j] == '.' && s[i][j + 1] == '#' && !vis[i][j]) {
                int a = 1, b = 1;
                for (int k = j + 2; k <= m - 2; k++)
                    if (s[i][k] == '#')a++;
                    else break;
                for (int k = i + 1; k <= n - 2; k++)
                    if (s[k][j + 1] == '#')b++;
                    else break;

                int x = 2 * a - b, y = 2 * b - 3 * a;
                if (x <= 0 || y <= 0)continue;

                int gg = 0;
                for (int k = j; k <= j + a + 1; k++)
                    if (s[i - 1][k] == '#' || s[i + b][k] == '#') {
                        gg++;
                        break;
                    }
                if (gg)continue;
                for (int k = i; k <= i + b - 1; k++)
                    if (s[k][j] == '#' || s[k][j + a + 1] == '#') {
                        gg++;
                        break;
                    }
                if (gg)continue;

                int cur = 0;
                if (s[i][j + x + 1] == '#' && s[i + x + y][j + x + 1] == '#' && s[i + 2 * (x + y)][j + x + 1] == '.')cur = 1;
                if (s[i][j + x + 1] == '#' && s[i + x + y][j + x + 1] == '#' && s[i + 2 * (x + y)][j + x + 1] == '#')cur = 2;
                if (s[i][j + x + 1] == '#' && s[i + x + y][j + x + 1] == '.' && s[i + 2 * (x + y)][j + x + 1] == '#')cur = 3;

                if (!cur)continue;

                //printf("%d %d %d\n",i,j,cur);

                if (find(i, j + 1, x, y, cur - 1)) {
                    for (int visx = i - 1; visx <= i + b; visx++)
                        for (int visy = j; visy <= j + a + 1; visy++)
                            vis[visx][visy]++;
                    if (cur == 1)ansa++;
                    else if (cur == 2)ansb++;
                    else ansc++;
                }

            }
    /*for(int i=1;i<=n;i++,printf("\n"))
        for(int j=1;j<=m;j++)printf("%d",vis[i][j]);*/
    printf("%d %d %d\n", ansa, ansb, ansc);
}

J：

看都看不懂的奇怪数学题，像是乱搞

K：

solver：zyh

#include <bits/stdc++.h>
using namespace std;
char str[1001];
int dp[1001][1001];
long long strhash[1001];
long long M = 1000000007;
long long p[1001];
long long getHash(int l, int r) {
    l++; r++;
    return (strhash[r] - (strhash[l - 1] * p[r - l + 1]) % M + M) % M;
}
int getKey(char ch) {
    if (ch >= 'a' && ch <= 'z') return ch - 'a' + 1;
    if (ch >= 'A' && ch <= 'Z') return ch - 'A' + 27;
    return ch - '0' + 54;
}
int solve(int l, int r) {
    if (~dp[l][r]) return dp[l][r];
    if (l == r) {
        dp[l][r] == 1;
        return 1;
    }
    int ans = 99999999;
    for (int i = 1; i <= r - l; ++i) {
        int j;
        long long rep = getHash(l, l + i - 1);
        for (j = l; j <= r - i + 1; j += i) if (rep != getHash(j, j + i - 1)) break;
        int f1, f2;
        f1 = f2 = 0;
        f1 = solve(l, l + i - 1);
        if (j <= r) f2 = solve(j, r);
        ans = min(ans, f1 + f2);
    }
    dp[l][r] = ans;
    return ans;
}
int main() {
    int len;
    scanf("%d", &len);
    scanf("%s", str);
    p[0] = 1;
    for (int i = 1; i <= len; ++i) p[i] = p[i - 1] * 71 % M;
    strhash[0] = 0;
    for (int i = 1; i <= len; ++i) strhash[i] = ((strhash[i - 1] * 71) % M + getKey(str[i - 1])) % M;
    //cout<<getHash(0,10)<<' '<<getHash(11,21)<<endl;
    memset(dp, -1, sizeof(dp));
    printf("%d\n", solve(0, len - 1));
}