Codeforces Round #619 (Div. 2)

contest

A

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
using namespace std;
string a, b , c;
void work()
{
    for(int i = 0;i < a.size();i ++)
    {
        if(c[i] != a[i] && c[i] != b[i])
        {
            cout << "NO" << endl;
            return;
        }
    }
    cout << "YES" << endl;
}
int main()
{
    int t = 0;
    cin >> t;
    while(t--)
    {
        cin >> a >> b >> c;
        work();
    }
    return 0;
}

B

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
using namespace std;
const int N = 100005;
int arr[N], n;

void work()
{
    int base = 0;
    vector<int> v;
    for(int i = 0;i < n - 1;i ++)
    {
        if(arr[i] == -1 && arr[i + 1] != -1)v.push_back(arr[i + 1]);
        else if(arr[i] != -1 && arr[i + 1] == -1)v.push_back(arr[i]);
        else if(arr[i] != -1 && arr[i + 1] != -1)base = max(base,abs(arr[i] - arr[i + 1]));
    }   
    if(v.empty())
    {
        printf("0 0\n");
        return;
    }
    sort(v.begin(),v.end());
    int k = (v.back() + *v.begin()) / 2;
    printf("%d %d\n",max({v.back() - k, k - v[0], base}),k);
    return;
}
int main()
{
    int t = 0;
    cin >> t;
    while(t--)
    {
        cin >> n;
        for(int i = 0;i < n;i ++)
        {
            scanf("%d",&arr[i]);
        }
        work();
    }
    return 0;
}

C

排列组合 隔板法 尝试让0的分布尽可能均匀而不是只考虑1

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>

using namespace std;
typedef long long ll;
ll n , m;
void work()
{
    ll ans = (n + 1) * n / 2,cnt = (n - m)/(m + 1);
    ans -= cnt * (cnt+1)/2*(m+1-(n-m)%(m+1)) + (cnt+1)*(cnt+2)/2*((n-m)%(m+1));
    cout << ans << endl;
}
int main()
{
    int t;
    cin >> t;
    while(t--)
    {
        scanf("%lld %lld",&n,&m);
        work();
    }
    return 0;
}

Codeforces Round #619 (Div. 2)

原文：https://www.cnblogs.com/wlw-x/p/12310979.html