2020 年 “联想杯”全国高校程序设计在线邀请赛暨第三届上海理工大学程序设计竞赛

目录

• A. Archmage
• B. Bamboo Leaf Rhapsody
• C. Cheat Sheet
• D. Disaster Recovery
• H. Hay Mower
• L. Lottery Tickets

A. Archmage

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main() {
    int t; cin >> t;
    while (t--) {
        ll n, m, x, y; cin >> n >> m >> x >> y;
        if (y >= x) cout << m << endl;
        else cout << min(m, (n + (m-1)*y)/x) << endl;
    }
    return 0;
}

B. Bamboo Leaf Rhapsody

#include <bits/stdc++.h>
using namespace std;
int main() {
    int n; scanf("%d",&n);
    double ans = 0x3f3f3f3f;
    for (int i = 1; i <= n; ++i) {
        double x, y, z; scanf("%lf%lf%lf",&x,&y,&z);
        ans = min(ans,sqrt(x*x+y*y+z*z));
    }
    printf("%.3lf\n",ans);
    return 0;
}

C. Cheat Sheet

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e3+5;
set<string> se;
vector<string> ve;
bool cmp(string x, string y) {
    return x.size() < y.size();
}
int main() {
    int n, m; cin >> n >> m;
    for (int i = 1; i <= m; ++i) {
        string s; cin >> s;
        se.insert(s);
    }
    for (auto r : se) ve.push_back(r);
    sort(ve.begin(),ve.end(),cmp);
    int ans = 0;
    for (int i = 0; i < ve.size(); ++i) {
        n -= ve[i].size();
        if (n >= 0) ans++;
        n--;
    }
    cout << ans << endl;
    return 0;
}

D. Disaster Recovery

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 1e5+5;

struct edge {
    int u, v;
};
bool cmp(const edge x, const edge y) {
    if (x.v != y.v) return x.v < y.v;
    return x.u < y.u;
}
vector<edge> ve;

int n, m;
int fa[maxn], d[maxn];
int find(int x) {
    if (fa[x] != x) fa[x] = find(fa[x]);
    return fa[x];
}
int main() {
    cin >> n >> m;
    for (int i = 1; i <= n; ++i) fa[i] = i;
    for (int i = 0; i < m; ++i) {
        int u, v; cin >> u >> v;
        if (u > v) swap(u,v);
        ve.push_back(edge{u,v});
    }
    sort(ve.begin(),ve.end(),cmp);
    for (int i = 0; i < m; ++i) {
        int u = ve[i].u, v = ve[i].v;
        int fu = find(u), fv = find(v);
        if (fu != fv) {
            fa[fu] = fv;
            ++d[u], ++d[v];
        }
    }
    int ans = 0;
    for (int i = 1; i <= n; ++i) {
        ans = max(ans,d[i]);
    }
    cout << ans << endl;
    return 0;
}

H. Hay Mower

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 505;
const int p = 998244353;
ll r[maxn], c[maxn];
ll a[maxn][maxn];
int main() {
    int n, m, k; cin >> n >> m >> k;
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j) {
            cin >> a[i][j];
        }
    }
    while (k--) {
        char ch; int xy; ll t;
        cin >> ch >> xy >> t;
        if (ch == 'r') r[xy] = t;
        else c[xy] = t;
    }
    ll ans = 0;
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j) {
            ans = (ans + (max(r[i],c[j])%p)*(a[i][j]%p)%p)%p;
        }
    }
    cout << ans << endl;
    return 0;
}

L. Lottery Tickets

#include <bits/stdc++.h>
using namespace std;
int c[10];
int a[] = {00,20,12,32,40,24,44,52,60,16,36,64,56,72,76,80,28,84,68,88,92,96};
int main() {
    int t; cin >> t;
    while (t--) {
        int cnt = 0;
        for (int i = 0; i <= 9; ++i) {
            cin >> c[i];
            cnt += c[i];
        }
        if (cnt == c[0]) {
            cout << 0 << endl;
            continue;
        }
        bool flag = false;
        int x, y;
        for (int i = 0; i < 22; ++i) {
            x = a[i]/10, y = a[i]%10;
            if (x == y && c[x] >= 2) {
                c[x] -= 2;
                flag = true;
                break;
            }
            if (x != y && c[x] >= 1 && c[y] >= 1) {
                c[x]--; c[y]--;
                flag = true;
                break;
            }
        }
        if (flag) {
            for (int i = 9; i >= 0; --i) {
                while (c[i]--) cout << i;
            }
            cout << x << y << endl;
            continue;
        }
        if (c[0] >= 1) cout << 0 << endl;
        else if (c[4] >= 1) cout << 4 << endl;
        else if (c[8] >= 1) cout << 8 << endl;
        else cout << -1 << endl;
    }
    return 0;
}