1327C - Game with Chips - CodeForces Solution

#include <bits/stdc++.h>

#define int long long int
#define nl "\n"
#define all(x) x.begin(), x.end()

using namespace std;



void Hck()
{
    int n, m, k;
    cin >> n >> m >> k;
    int k2 = k;
    int kk = k;
    map<pair<int,int>,int> mp;
    string ans = "";
    int mxx = INT_MIN;
    int mxy = INT_MIN;

    while(k2--){
        int a,b;
        cin >> a >> b;
        mxx = max(mxx, a);
        mxy = max(mxy, b);
        mp[{a,b}]++;
    }
    int cnt = 0;
    while(k--){
        int a,b;
        cin >> a >> b;
        if(mp.count({a,b}) && mp[{a,b}] == kk){
            cnt++;
        }
    }
    for(int i = 0; i <= mxx-1; i++){
        ans += 'U';
    }
    for(int i = 0; i <= mxy-1; i++){
        ans += 'L';
    }
    for(int i = 0; i < n; i++){
        for(int j = 0; j < m-1; j++){
            if(i % 2 == 0){
                ans += 'R';
            }
            else
                ans += 'L';
        }
        if(i<n-1)
        ans += 'D';
    }
    if(cnt == kk){
        cout << 0 << nl;
        return;
    }
    // cout << cnt  << " " << k << nl;

    cout << ans.size() << nl;
    cout << ans << nl;

}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int tt = 1;
    // cin >> tt;
    for (int i = 1; i <= tt; i++)
    {
        Hck();
    }

    return 0;
}