CodeForces Round #555 Div.3

A. Reachable Numbers

代码：

#include <bits/stdc++.h>
using namespace std;

const int maxn = 1e9 + ;
int N;
set<int> s;

int main() {
    scanf("%d", &N);
    while(s.find(N) == s.end()) {
        s.insert(N);
        N += ;
        while(N %  == ) N /= ;
    }

    printf("%d\n", (int) s.size());

    return ;
}

B. Long Number

代码：

#include <bits/stdc++.h>
using namespace std;

int N;
string s;
int a[];

int main() {
    scanf("%d", &N);
    cin >> s;
    for(int i = ; i <= ; i ++) {
        int x;
        scanf("%d", &x);
        a[i] = x;
    }

    for(int i = ; i < N; i ++) {
        if(a[s[i] - ''] > s[i] - '') {
            for(int j = i; j < N; j ++) {
                if(a[s[j] - ''] >= s[j] - '')
                    s[j] = a[s[j] - ''] + '';
                else break;
            }
            break;
        }
    }

    cout << s << endl;

    return ;
}

C1. Increasing Subsequence (easy version)

代码：

#include <bits/stdc++.h>
using namespace std;

const int maxn = 2e5 + ;
int N;
int a[maxn];

int main() {
    scanf("%d", &N);
    for(int i = ; i < N; i ++)
        scanf("%d", &a[i]);
    string ans = "";

    int l = , r = N - , pos = ;
    while(l <= r) {
        if(a[l] < a[r]) {
            if(a[l] > pos) {
                pos = a[l];
                l ++;
                ans += 'L';
            } else if(a[r] > pos) {
                pos = a[r];
                r --;
                ans += 'R';
            } else break;
        } else {
            if(a[r] > pos) {
                pos = a[r];
                r --;
                ans += 'R';
            } else if(a[l] > pos) {
                pos = a[l];
                l ++;
                ans += 'L';
            } else break;
        }
    }

    printf("%d\n", ans.length());
    cout << ans << endl;

    return ;
}

C2. Increasing Subsequence (hard version)

代码（在两边一样的情况下只能选左或右跑了）：

#include <bits/stdc++.h>
using namespace std;

const int maxn = 2e5 + ;
int N;
int pos = ;
int a[maxn];
string ans1 = "", ans2 = "", ans = "";

string Left(int st, int en, string s) {
    string t = s;
    int l = st, r = en;
    while(l <= r) {
        if(a[l] > pos) {
            pos = a[l];
            l ++;
            t += 'L';
        } else break;
    }
    return t;
}

string Right(int st, int en, string s) {
    string t = s;
    int l = st, r = en;
    while(l <= r) {
        if(a[r] > pos) {
            pos = a[r];
            r --;
            t += 'R';
        } else break;
    }
    return t;
}

int main() {
    scanf("%d", &N);
    for(int i = ; i < N; i ++)
        scanf("%d", &a[i]);

    int l = , r = N - ;
    int tp = ;
    while(l <= r) {
        if(a[l] < a[r]) {
            if(a[l] > pos) {
                pos = a[l];
                l ++;
                ans += 'L';
            } else if(a[r] > pos) {
                pos = a[r];
                r --;
                ans += 'R';
            } else break;
        } else if(a[l] > a[r]) {
            if(a[r] > pos) {
                pos = a[r];
                r --;
                ans += 'R';
            } else if(a[l] > pos) {
                pos = a[l];
                l ++;
                ans += 'L';
            } else break;
        } else {
            int poo = pos;
            ans1 = ans, ans2 = ans;
            ans1 = Left(l, r, ans);
            pos = poo;
            ans2 = Right(l, r, ans);
            if(ans1.length() > ans2.length())
                //cout << ans1 << endl;
                ans = ans1;
            else //cout << ans2 << endl;
                ans = ans2;
            break;
        }
    }

    printf("%d\n", ans.length());
    cout <<ans <<endl;

    return ;
}

/*

15
37504 79054 80071 95721 135743 164345 189260 190810 191657 196168 200000 200000 190810 190018 185437

*/

E. Minimum Array

代码：

#include <bits/stdc++.h>
using namespace std;

const int maxn = 2e5 + ;
int N;
int a[maxn], c[maxn];

int main() {
    multiset<int> s;
    scanf("%d", &N);
    for(int i = ; i <= N; i ++)
        scanf("%d", &a[i]);
    for(int i = ; i <= N; i ++) {
        int x;
        scanf("%d", &x);
        s.insert(x);
    }
    for(int i = ; i <= N; i ++) {
        int now = N - a[i] % N;
        multiset <int>::iterator it = s.lower_bound(now);
        if(it == s.end()) it = s.begin();
        c[i] = (a[i] + (*it)) % N;
        s.erase(it);
    }

    for(int i = ; i <= N; i ++)
        printf("%d%s", c[i], i != N ? " " : "\n");

    return ;
}

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