#include <bits/stdc++.h>
#define ID(x, y) (((x) - 1) * m + (y))
#define pb emplace_back
#define fst first
#define scd second
#define mkp make_pair
#define mems(a, x) memset((a), (x), sizeof(a))

using namespace std;
typedef long long ll;
typedef double db;
typedef unsigned long long ull;
typedef long double ldb;
typedef pair<ll, ll> pii;

const int maxn = 400100;

int n, m, K;
bool flag;
char ans[maxn];

struct node {
	int x1, y1, x2, y2, x;
} a[maxn];

inline void print() {
	puts("Yes");
	if (flag) {
		for (int i = 1; i <= m; ++i) {
			for (int j = 1; j <= n; ++j) {
				char c = ans[ID(j, i)];
				if (c == 'D') {
					c = 'R';
				} else if (c == 'U') {
					c = 'L';
				} else if (c == 'R') {
					c = 'D';
				} else {
					c = 'U';
				}
				putchar(c);
			}
			putchar('\n');
		}
	} else {
		for (int i = 1; i <= n; ++i) {
			for (int j = 1; j <= m; ++j) {
				putchar(ans[ID(i, j)]);
			}
			putchar('\n');
		}
	}
}

namespace Sub1 {
	int fa[maxn];
	
	int find(int x) {
		return fa[x] == x ? x : fa[x] = find(fa[x]);
	}
	
	void solve() {
		if (n & 1) {
			flag ^= 1;
			swap(n, m);
			for (int i = 1; i <= K; ++i) {
				swap(a[i].x1, a[i].y1);
				swap(a[i].x2, a[i].y2);
			}
		}
		if (n % 2 == 0 && m % 2 == 0 && n > m) {
			flag ^= 1;
			swap(n, m);
			for (int i = 1; i <= K; ++i) {
				swap(a[i].x1, a[i].y1);
				swap(a[i].x2, a[i].y2);
			}
		}
		bool fl = 1;
		for (int i = 1; i <= K && fl; ++i) {
			fl &= (a[i].x1 == a[i].x2);
		}
		if (fl) {
			for (int i = 1; i <= m; ++i) {
				ans[ID(1, i)] = 'D';
				ans[ID(2, i)] = 'U';
			}
			print();
			return;
		}
		if (n == 2) {
			for (int i = 1; i <= m; ++i) {
				fa[i] = i;
			}
			for (int i = 1; i <= K; ++i) {
				if (a[i].y1 > a[i].y2) {
					swap(a[i].y1, a[i].y2);
				}
				for (int j = find(a[i].y1); j < a[i].y2; j = find(j)) {
					fa[j] = j + 1;
				}
			}
			if (find(1) == find(m)) {
				puts("No");
				return;
			}
			for (int i = 1; i <= m; ++i) {
				ans[ID(1, i)] = 'D';
				ans[ID(2, i)] = 'U';
			}
			int x = find(1);
			ans[ID(1, x)] = ans[ID(2, x)] = 'R';
			ans[ID(1, x + 1)] = ans[ID(2, x + 1)] = 'L';
			print();
			return;
		}
		for (int i = 1; i <= n; i += 2) {
			if (i % 4 == 1) {
				for (int j = 1; j <= m - 2; ++j) {
					ans[ID(i, j)] = 'D';
					ans[ID(i + 1, j)] = 'U';
				}
				ans[ID(i, m - 1)] = 'R';
				ans[ID(i, m)] = 'L';
				ans[ID(i + 1, m - 1)] = 'R';
				ans[ID(i + 1, m)] = 'L';
			} else {
				for (int j = 3; j <= m; ++j) {
					ans[ID(i, j)] = 'D';
					ans[ID(i + 1, j)] = 'U';
				}
				ans[ID(i, 1)] = 'R';
				ans[ID(i, 2)] = 'L';
				ans[ID(i + 1, 1)] = 'R';
				ans[ID(i + 1, 2)] = 'L';
			}
		}
		print();
	}
}

int d[maxn], f[maxn];
vector<int> add[maxn], del[maxn];

inline void work(int l, int r) {
	if (n % 2 == 0) {
		for (int i = 1; i <= n; i += 2) {
			for (int j = l; j <= r; ++j) {
				ans[ID(i, j)] = 'D';
				ans[ID(i + 1, j)] = 'U';
			}
		}
	} else {
		for (int i = 1; i <= n - 2; ++i) {
			for (int j = l; j <= r; j += 2) {
				ans[ID(i, j)] = 'R';
				ans[ID(i, j + 1)] = 'L';
			}
		}
		for (int i = l; i <= r; ++i) {
			ans[ID(n - 1, i)] = 'D';
			ans[ID(n, i)] = 'U';
		}
	}
}

void solve() {
	flag = 0;
	scanf("%d%d%d", &n, &m, &K);
	if (n > m) {
		flag = 1;
		swap(n, m);
	}
	bool fl = 1;
	for (int i = 1; i <= K; ++i) {
		scanf("%d%d%d%d%d", &a[i].x1, &a[i].y1, &a[i].x2, &a[i].y2, &a[i].x);
		fl &= a[i].x;
		if (flag) {
			swap(a[i].x1, a[i].y1);
			swap(a[i].x2, a[i].y2);
		}
	}
	if (fl) {
		Sub1::solve();
		return;
	}
	if (n == 1) {
		fl = 1;
		for (int i = 1; i <= K && fl; ++i) {
			int x = (a[i].y1 ^ 1);
			int t = (a[i].y1 == a[i].y2 || x == a[i].y2);
			fl &= (a[i].x == t);
		}
		if (fl) {
			for (int i = 1; i <= m; ++i) {
				putchar((i & 1) ? 'R' : 'L');
			}
		} else {
			puts("No");
		}
		return;
	}
	mems(d, 0);
	mems(f, -0x3f);
	for (int i = 1; i <= K; ++i) {
		int l = min(a[i].y1, a[i].y2), r = max(a[i].y1, a[i].y2);
		// printf("l, r: %d %d\n", l, r);
		if (a[i].x) {
			++d[l + 1];
			--d[r + 1];
		} else {
			f[r] = max(f[r], l);
		}
	}
	for (int i = 1; i <= m; ++i) {
		d[i] += d[i - 1];
		vector<int>().swap(add[i]);
		vector<int>().swap(del[i]);
	}
	set<int> S;
	fl = (f[1] < 0);
	S.insert(0);
	for (int i = 2; i <= m && fl; ++i) {
		int x = *S.begin();
		if (!d[i] && !(n & i & 1) && x != i - 1) {
			add[i].pb(i);
			S.insert(i);
		}
		while (S.size() && *S.begin() <= f[i]) {
			del[i].pb(*S.begin());
			S.erase(S.begin());
		}
		// printf("%d %d\n", i, (int)S.size());
		fl &= (!S.empty());
	}
	if (fl) {
		int p = m;
		for (int i = m; i; --i) {
			if (i == p) {
				work(*S.begin() + 1, i == m ? m : i - 1);
				p = *S.begin() - 1;
				if (p >= 1) {
					for (int j = 1; j <= n; ++j) {
						ans[ID(j, p)] = 'R';
						ans[ID(j, p + 1)] = 'L';
					}
				}
			}
			for (int j : del[i]) {
				S.insert(j);
			}
			for (int j : add[i]) {
				S.erase(j);
			}
		}
		print();
		return;
	}
	flag ^= 1;
	swap(n, m);
	for (int i = 1; i <= K; ++i) {
		swap(a[i].x1, a[i].y1);
		swap(a[i].x2, a[i].y2);
	}
	mems(d, 0);
	mems(f, -0x3f);
	for (int i = 1; i <= K; ++i) {
		int l = min(a[i].y1, a[i].y2), r = max(a[i].y1, a[i].y2);
		if (a[i].x) {
			++d[l + 1];
			--d[r + 1];
		} else {
			f[r] = max(f[r], l);
		}
	}
	for (int i = 1; i <= m; ++i) {
		d[i] += d[i - 1];
		vector<int>().swap(del[i]);
		vector<int>().swap(add[i]);
	}
	S.clear();
	fl = (f[1] < 0);
	S.insert(0);
	for (int i = 2; i <= m && fl; ++i) {
		int x = *S.begin();
		if (!d[i] && !(n & i & 1) && x != i - 1) {
			add[i].pb(i);
			S.insert(i);
		}
		while (S.size() && *S.begin() <= f[i]) {
			del[i].pb(*S.begin());
			S.erase(S.begin());
		}
		fl &= (!S.empty());
	}
	if (fl) {
		int p = m;
		for (int i = m; i; --i) {
			if (i == p) {
				work(*S.begin() + 1, i == m ? m : i - 1);
				p = *S.begin() - 1;
				if (p >= 1) {
					for (int j = 1; j <= n; ++j) {
						ans[ID(j, p)] = 'R';
						ans[ID(j, p + 1)] = 'L';
					}
				}
			}
			for (int j : del[i]) {
				S.insert(j);
			}
			for (int j : add[i]) {
				S.erase(j);
			}
		}
		print();
		return;
	}
	puts("No");
}

int main() {
	int T = 1;
	scanf("%d", &T);
	for (int i = 1; i <= T; ++i) {
		printf("Case #%d: ", i);
		solve();
	}
	return 0;
}