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Codeforces Round #631 Editorial

Revision en4, by dreamoon_love_AA, 2020-04-03 21:43:34

Div.1 C and E is still under construction...

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author's code:

#include<cstdio>
const int MAX_V = 201;
bool achieve[MAX_V];
void solve() {
    int n, x;
    scanf("%d%d", &n, &x);
    for(int i = 1; i <= n + x; i++) {
        achieve[i] = false;
    }
    for(int i = 1; i <= n; i++) {
        int ranking;
        scanf("%d", &ranking);
        achieve[ranking] = true;
    }
    for(int k = n + x; k > 0; k--) {
        int v = 0;
        for(int i = 1; i <= k; i++) {
            if(!achieve[i]) v++;
        }
        if(v <= x) {
            printf("%d\n", k);
            return;
        }
    }
}
int main() {
    int T;
    scanf("%d", &T);
    while(T--) solve();
    return 0;
}
Tutorial is loading...

author's code:

#include<cstdio>
const int SIZE = 200000;
int p[SIZE];
int ans[SIZE][2];
int ans_cnt;
bool judge(int a[], int n){
    static int used[SIZE+1];
    for(int i = 1; i <= n; i++) used[i] = 0;
    for(int i = 0; i < n; i++) used[a[i]] = 1;
    for(int i = 1; i <= n; i++) {
        if(!used[i]) return 0;
    }
    return 1;
}
bool judge(int len1, int n){
    return judge(p, len1) && judge(p + len1, n &mdash; len1);
}
int main() {
    int t = 0;
    scanf("%d", &t);
    while(t--) {
        ans_cnt = 0;
        int n;
        scanf("%d", &n);
        int ma=0;
        for(int i = 0; i < n; i++) {
            scanf("%d", &p[i]);
            if(ma < p[i]) ma = p[i];
        }
        if(judge(n &mdash; ma,n)) {
            ans[ans_cnt][0] = n &mdash; ma;
            ans[ans_cnt++][1] = ma;
        }
        if(ma * 2 != n && judge(ma,n)) {
            ans[ans_cnt][0] = ma;
            ans[ans_cnt++][1] = n &mdash; ma;
        }
        printf("%d\n", ans_cnt);
        for(int i = 0; i < ans_cnt; i++) {
            printf("%d %d\n", ans[i][0], ans[i][1]);
        }
    }
    return 0;
}
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author's code:

#include<bits/stdc++.h>
const int SIZE = 100002;
int len[SIZE];
long long suffix_sum[SIZE];
void err() {puts("-1");}
void solve() {
    int N, M;
    scanf("%d%d", &N, &M);
    for(int i = 1; i <= M; i++) {
        scanf("%d", &len[i]);
        if(len[i] + i &mdash; 1 > N) {
            err();
            return;
        }
    }
    for(int i = M; i > 0; i--) {
        suffix_sum[i] = suffix_sum[i + 1] + len[i];
    }
    if(suffix_sum[1] < N) {
        err();
        return;
    }
    for(int i = 1; i <= M; i++) {
        printf("%lld", std::max((long long)i, N &mdash; suffix_sum[i] + 1));
        if(i < M) putchar(' ');
        else puts("");
    }
}
int main() {
    solve();
    return 0;
}
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author's code:

#include<bits/stdc++.h>
void solve(){
    int d, m;
    scanf("%d%d",&d, &m);
    long long answer=1;
    for(int i = 0; i < 30; i++) {
        if(d < (1 << i)) break;
        answer = answer * (std::min((1 << (i+1)) &mdash; 1, d) &mdash; (1 << i) + 2) % m;
    }
    answer--;
    if(answer < 0) answer += m;
    printf("%lld\n",answer);
}
int main() {
    int T;
    scanf("%d", &T);
    while(T--) {
        solve();
    }
}
Tutorial is loading...

author's code:

#include<bits/stdc++.h>
using namespace std;
const int SIZE = 1<<20;
int INF = 1000000001;
pair<int, int> a[SIZE];
int final_v[SIZE];
bool used[SIZE];
int h, g;
void pull(int id) {
    while(a[id] > min(a[id<<1], a[(id<<1)|1])) {
        if(a[id<<1] < a[(id << 1) | 1]) {
            swap(a[id<<1], a[id]);
            id <<= 1;
        }
        else {
            swap(a[(id<<1)|1], a[id]);
            id = (id << 1) | 1;
        }
        if(id >= (1 << h)) return;
    }
}
void solve() {
    scanf("%d%d", &h, &g);
    long long an = 0;
    for(int i = 1; i < (1 << h); i++) {
        used[i] = 0;
        scanf("%d", &a[i].first);
        a[i].second = i;
        final_v[i] = 0;
    }
    h--;
    for(int lv = h &mdash; 1; lv >= 0; lv--) {
        int ll = 1 << lv;
        int rr = 1 << (lv + 1);
        for(int i = ll; i < rr; i++) {
            pair<int, int> tmp = a[i];
            int bot = i << (h &mdash; lv);
            a[i] = a[bot];
            a[bot] = make_pair(INF, 0);
            pull(i);
            if(lv < g) {
                int need_mi = max(final_v[i * 2], final_v[i * 2 + 1]);
                while(a[i].first < need_mi) {
                    a[i] = make_pair(INF, 0);
                    pull(i);
                }
                an += final_v[i] = a[i].first;
                used[a[i].second] = 1;
                a[i] = tmp;
                pull(i);
            }
            else {
                a[bot] = tmp;
            }
        }
    }
    printf("%lld\n", an);
    bool first_time = true;
    for(int i = (1 << (h + 1)) &mdash; 1; i > 0; i--) {
        if(!used[i]) {
            if(!first_time) printf(" ");
            else first_time = false;
            printf("%d", i);
        }
    }
    puts("");
}
int main(){
    int T;
    scanf("%d", &T);
    while(T--) solve();
    return 0;
}
Tutorial is loading...

author's code:

#include<bits/stdc++.h>
using namespace std;
const int SIZE = 2e5+10;
char s[SIZE];
int cnt[SIZE];
int cc[26];
int all_cnt;
int ma;
void update_ma() {
    while(ma > 0 && !cnt[ma]) ma--;
}
void dec1(int id) {
    cnt[cc[id]]--;
    cc[id]--;
    cnt[cc[id]]++;
}
pair<int, int> stk[SIZE];
int sn;
int m;
int now;
int last_len;
void add(int i, bool flag) {
    if(flag) {
        dec1(stk[sn &mdash; 1].second);
        dec1(stk[i].second);
        all_cnt -= 2;
        printf("%d %d\n",now + 1, now + stk[i].first);
        update_ma();
        sn--;
        now -= stk[sn].first;
        if(i + 1 < m) {
            stk[i + 1].first += stk[sn].first;
        }
        else{
            last_len += stk[sn].first;
        }
    }
    else {
        stk[sn++] = stk[i];
        now += stk[i].first;
    }
}
void solve(){
    scanf("%s", s);
    int n = strlen(s);
    all_cnt = 0;
    int lt = 0;
    m = 0;
    for(int i = 1; i < n; i++) {
        if(s[i] == s[i &mdash; 1]) {
            cc[s[i] &mdash; 'a']++;
            all_cnt++;
            stk[m++] = make_pair(i &mdash; lt, (int)(s[i] &mdash; 'a'));
            lt = i;
        }
    }
    last_len = n &mdash; lt;
    ma = 0;
    for(int i = 0; i < 26; i++) {
        cnt[cc[i]]++;
        ma = max(ma, cc[i]);
    }
    printf("%d\n", 1 + max(ma, (all_cnt + 1) / 2));
    if(ma * 2 < all_cnt) {
        sn = now = 0;
        for(int i = 0; i < m; i++) {
            add(i, sn && stk[sn &mdash; 1].second != stk[i].second && ma * 2 < all_cnt);
        }
        m = sn;
    }
    int main_id = -1;
    for(int i = 0; i < 26; i++) {
        if(cc[i] == ma) main_id = i;
    }
    sn = now = 0;
    for(int i = 0; i < m; i++) {
        add(i, sn && ((stk[sn &mdash; 1].second == main_id) ^ (stk[i].second == main_id)));
    }
    for(int i = 0; i < sn; i++) {
        printf("%d %d\n",1 ,stk[i].first);
    }
    printf("%d %d\n", 1, last_len);
    memset(cc, 0, sizeof(cc));
    memset(cnt, 0, sizeof(int) * (ma + 1));
}
int main(){
    int T;
    scanf("%d", &T);
    for(int i = 1; i <= T; i++) solve();
    return 0;
}
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History

 
 
 
 
Revisions
 
 
  Rev. Lang. By When Δ Comment
en21 English dreamoon_love_AA 2020-04-05 21:15:08 1 Tiny change: '5] provide proof for' -> '5] provides proof for'
en20 English dreamoon_love_AA 2020-04-05 21:14:23 143
en19 English dreamoon_love_AA 2020-04-05 20:31:48 53 Tiny change: '#### **Div.1 E is still under construction...**\n\n[tutorial:' -> '[tutorial:'
en18 English dreamoon_love_AA 2020-04-05 17:13:21 8807
en17 English dreamoon_love_AA 2020-04-05 07:59:53 159 Tiny change: 'takk].\n\n<spoil' -> 'takk].\n\n\n\n<spoil'
en16 English dreamoon_love_AA 2020-04-05 01:12:06 2 Tiny change: '# **Div.1 C E is stil' -> '# **Div.1 E is stil'
en15 English dreamoon_love_AA 2020-04-05 00:46:24 13
en14 English dreamoon_love_AA 2020-04-04 22:23:28 1518
en13 English dreamoon_love_AA 2020-04-04 22:16:37 3500
en12 English dreamoon_love_AA 2020-04-04 00:10:34 4
en11 English dreamoon_love_AA 2020-04-04 00:09:37 9 (published)
en10 English dreamoon_love_AA 2020-04-04 00:05:13 20 Tiny change: 'oiler>\n\n' -> 'oiler>\n\n\n[tutorial:1329E]\n'
en9 English dreamoon_love_AA 2020-04-04 00:04:54 18 Tiny change: 'oiler>\n\n[tutorial:1329E]\n' -> 'oiler>\n\n' (saved to drafts)
en8 English dreamoon_love_AA 2020-04-03 22:16:10 144
en7 English dreamoon_love_AA 2020-04-03 22:13:29 8 Tiny change: 'long)i, N &mdash; suffix_su' -> 'long)i, N - suffix_su'
en6 English dreamoon_love_AA 2020-04-03 21:56:32 238
en5 English dreamoon_love_AA 2020-04-03 21:44:17 5 Tiny change: '1 C and E is still und' -> '1 C and E are still und' (published)
en4 English dreamoon_love_AA 2020-04-03 21:43:34 12
en3 English dreamoon_love_AA 2020-04-03 21:42:38 7309
en2 English dreamoon_love_AA 2020-04-03 21:35:25 156
en1 English dreamoon_love_AA 2020-04-03 21:34:20 307 Initial revision (saved to drafts)