Problem:
Score : 700 points

Problem Statement

We have a grid with H rows and W columns of squares.
We will represent the square at the i-th row from the top and j-th column from the left as (i,\ j).
Also, we will define the distance between the squares (i_1,\ j_1) and (i_2,\ j_2) as |i_1 - i_2| + |j_1 - j_2|.

Snuke is painting each square in red, yellow, green or blue.
Here, for a given positive integer d, he wants to satisfy the following condition:

No two squares with distance exactly d have the same color.

Find a way to paint the squares satisfying the condition.
It can be shown that a solution always exists.

Constraints

2 ≤ H, W ≤ 500

1 ≤ d ≤ H + W - 2

Input

Input is given from Standard Input in the following format:

H W d

Output

Print a way to paint the squares satisfying the condition, in the following format. If the square (i,\ j) is painted in red, yellow, green or blue, c_{ij} should be R, Y, G or B, respectively.

c_{11}c_{12}...c_{1W}
:
c_{H1}c_{H2}...c_{HW}

Sample Input 1

2 2 1

Sample Output 1

RY
GR

There are four pairs of squares with distance exactly 1.
As shown below, no two such squares have the same color.

(1,\ 1), (1,\ 2) : R, Y

(1,\ 2), (2,\ 2) : Y, R

(2,\ 2), (2,\ 1) : R, G

(2,\ 1), (1,\ 1) : G, R

Sample Input 2

2 3 2

Sample Output 2

RYB
RGB

There are six pairs of squares with distance exactly 2.
As shown below, no two such squares have the same color.

(1,\ 1) , (1,\ 3) : R , B

(1,\ 3) , (2,\ 2) : B , G

(2,\ 2) , (1,\ 1) : G , R

(2,\ 1) , (2,\ 3) : R , B

(2,\ 3) , (1,\ 2) : B , Y

(1,\ 2) , (2,\ 1) : Y , R

Solution in C (GCC 5.4.1) (judge verdict: Accepted)

/*
cat <<EOF >mistaken-paste
*/

#pragma GCC diagnostic ignored "-Wincompatible-pointer-types"
#define _USE_MATH_DEFINES

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <math.h>
#include <time.h>

#define BIG 2000000007
#define VERYBIG 2000000000000007LL

#define MOD 1000000007
#define FOD  998244353
typedef uint64_t ull;
typedef  int64_t sll;

#define N_MAX 1000000
#define M_MAX 200000

#ifdef __cplusplus
#include <queue>
#include <stack>
#include <tuple>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <functional>
#include <array>

using std::queue;
using std::priority_queue;
using std::stack;
using std::tuple;
using std::set;
using std::map;
using std::vector;
using std::greater;
using std::pair;
using std::string;

#endif

typedef struct {
	int32_t a;
	int32_t b;
} hw;

typedef struct {
	sll a;
	sll b;
} hwll;

typedef struct {
	sll a;
	sll b;
	sll c;
} hwllc;

typedef struct {
	hwll a;
	hwll b;
} linell;

ull n, m;
ull h, w;
ull k;
ull q;
sll va, vb, vc, vd, ve, vf;
ull ua, ub, uc, ud, ue, uf;
long double vra, vrb, vrc;
double vda, vdb, vdc;
char ch, dh;

ull umin (ull x, ull y) {
	return (x < y) ? x : y;
}

ull umax (ull x, ull y) {
	return (x > y) ? x : y;
}

sll smin (sll x, sll y) {
	return (x < y) ? x : y;
}

sll smax (sll x, sll y) {
	return (x > y) ? x : y;
}

ull gcd (ull x, ull y) {
	if (x < y) {
		return gcd(y, x);
	} else if (y == 0) {
		return x;
	} else {
		return gcd(y, x % y);
	}
}

ull bitpow (ull a, ull x, ull modulo) {
	ull result = 1;
	while (x) {
		if (x & 1) {
			result *= a;
			result %= modulo;
		}
		x /= 2;
		a = (a * a) % modulo;
	}
	return result;
}

ull divide (ull a, ull b, ull modulo) {
	return (a * bitpow(b, modulo - 2, modulo)) % modulo;
}

ull udiff (ull a, ull b) {
	if (a >= b) {
		return a - b;
	} else {
		return b - a;
	}
}

sll sdiff (sll a, sll b) {
	if (a >= b) {
		return a - b;
	} else {
		return b - a;
	}
}

int bitcount (ull n) {
	int result = 0;
	while (n) {
		if (n & 1) result++;
		n /= 2;
	}
	return result;
}

// double distance (sll x1, sll y1, sll x2, sll y2) {
// 	double xdist2, ydist2, origindist, dist;

// 	xdist2 = (x1 - x2) * (x1 - x2);
// 	ydist2 = (y1 - y2) * (y1 - y2);
// 	return sqrt(xdist2 + ydist2);
// }

int32_t pullcomp (const void *left, const void *right) {
	ull l = *(ull*)left;
	ull r = *(ull*)right;
	if (l < r) {
		return -1;
	}
	if (l > r) {
		return +1;
	}
	return 0;
}

int32_t psllcomp (const void *left, const void *right) {
	sll l = *(sll*)left;
	sll r = *(sll*)right;
	if (l < r) {
		return -1;
	}
	if (l > r) {
		return +1;
	}
	return 0;
}

int32_t pcharcomp (const void *left, const void *right) {
	char l = *(char*)left;
	char r = *(char*)right;
	if (l < r) {
		return -1;
	}
	if (l > r) {
		return +1;
	}
	return 0;
}

int32_t pdoublecomp (const void *left, const void *right) {
	double l = *(double*)left;
	double r = *(double*)right;
	if (l < r) {
		return -1;
	}
	if (l > r) {
		return +1;
	}
	return 0;
}

int32_t pstrcomp (const void *left, const void *right) {
	char* l = *(char**)left;
	char* r = *(char**)right;

	return strcmp(l, r);
}

int32_t phwllABcomp (const void *left, const void *right) {
	hwll l = *(hwll*)left;
	hwll r = *(hwll*)right;
	if (l.a < r.a) {
		return -1;
	}
	if (l.a > r.a) {
		return +1;
	}
	if (l.b < r.b) {
		return -1;
	}
	if (l.b > r.b) {
		return +1;
	}
	return 0;
}

int32_t phwllREVcomp (const void *left, const void *right) {
	hwll l = *(hwll*)left;
	hwll r = *(hwll*)right;
	if (l.b < r.b) {
		return -1;
	}
	if (l.b > r.b) {
		return +1;
	}
	if (l.a < r.a) {
		return -1;
	}
	if (l.a > r.a) {
		return +1;
	}
	return 0;
}

int32_t ptriplecomp (const void *left, const void *right) {
	hwllc l = *(hwllc*)left;
	hwllc r = *(hwllc*)right;

	if (l.a < r.a) {
		return -1;
	}
	if (l.a > r.a) {
		return +1;
	}
	if (l.b < r.b) {
		return -1;
	}
	if (l.b > r.b) {
		return +1;
	}
	if (l.c < r.c) {
		return -1;
	}
	if (l.c > r.c) {
		return +1;
	}
	return 0;
}

bool isinrange (sll left, sll x, sll right) {
	return (left <= x && x <= right);
}

bool isinrange_soft (sll left, sll x, sll right) {
	return (left <= x && x <= right) || (left >= x && x >= right);
}

// sll a[N_MAX];
sll a[3001][3001];
sll b[N_MAX];
// sll b[3001][3001];
sll c[N_MAX];
// sll d[N_MAX];
// sll e[N_MAX];
char s[N_MAX + 1];
// char s[3010][3010];
char t[N_MAX + 1];
// char t[3010][3010];
// hwll xy[N_MAX];
// sll table[1000][1000];


ull is_lms (bool isS[], ull i) {
	return ((i && !isS[i - 1] && isS[i]) ? 1 : 0);
}

void induced_sort (ull s[], sll sa[], bool isS[], ull lms[], ull n, ull lmscnt, ull ckind) {
	sll i, j;

	for (i = 0; i <= n; i++) {
		sa[i] = -1;
	}

	ull bucket[ckind + 1];
	for (i = 0; i <= ckind; i++) {
		bucket[i] = 0;
	}
	for (i = 0; i <= n; i++) {
		bucket[s[i]]++;
	}
	ull sum = 0;
	for (i = 0; i <= ckind; i++) {
		sum += bucket[i];
		bucket[i] = sum - bucket[i];
	}

	// put LMS
	ull cnt[ckind];
	for (i = 0; i < ckind; i++) {
		cnt[i] = 0;
	}
	for (i = lmscnt - 1; i >= 0; i--) {
		ull ch = s[lms[i]];
		sa[bucket[ch + 1] - 1 - cnt[ch]] = lms[i];
		// printf("LMSput: [%3llu] <- %3llu\n", bucket[ch + 1] - 1 - cnt[ch], lms[i]);
		// fflush(stdout);
		cnt[ch]++;
	}

	// put L-type
	memset(cnt, 0, sizeof(ull) * ckind);
	for (i = 0; i <= n; i++) {
		if (sa[i] < 0) continue;
		if (sa[i] == 0 || isS[sa[i] - 1]) continue;

		ull ch = s[sa[i] - 1];
		sa[bucket[ch] + cnt[ch]] = sa[i] - 1;
		// printf("  Lput: [%3llu] <- %3llu\n", bucket[ch] + cnt[ch], sa[i] - 1);
		// fflush(stdout);
		cnt[ch]++;
	}

	// put S-type
	memset(cnt, 0, sizeof(ull) * ckind);
	for (i = n; i >= 0; i--) {
		if (sa[i] < 0) continue;
		if (sa[i] == 0 || !isS[sa[i] - 1]) continue;

		ull ch = s[sa[i] - 1];
		sa[bucket[ch + 1] - 1 - cnt[ch]] = sa[i] - 1;
		// printf("  Sput: [%3llu] <- %3llu\n", bucket[ch + 1] - 1 - cnt[ch], sa[i] - 1);
		// fflush(stdout);
		cnt[ch]++;
	}
}

void sa_is (ull s[], sll sa[], ull n, ull ckind) {
	sll i;

	bool isS[n + 1];
	isS[n] = true;
	for (i = n - 1; i >= 0; i--) {
		if (s[i] < s[i + 1]) {
			isS[i] = true;
		} else if (s[i] > s[i + 1]) {
			isS[i] = false;
		} else {
			isS[i] = isS[i + 1];
		}
	}

	ull lms[n + 1], lmscnt = 0;
	for (i = 0; i <= n; i++) {
		if (is_lms(isS, i)) {
			lms[lmscnt++] = i;
		}
	}

	induced_sort(s, sa, isS, lms, n, lmscnt, ckind);

	ull lmssort[lmscnt], c = 0;
	for (i = 0; i <= n; i++) {
		ull v = sa[i];
		if (is_lms(isS, v)) {
			lmssort[c++] = v;
		}
	}

	ull nums[n + 1], num = 0;
	nums[lmssort[0]] = 0;
	bool isunique = true;
	for (i = 1; i < lmscnt; i++) {
		ull prev = lmssort[i - 1];
		ull curr = lmssort[i];

		bool issame = true;
		sll j = 0;
		while (true) {
			if (prev + j > n || curr + j > n || s[prev + j] != s[curr + j] || is_lms(isS, prev + j) != is_lms(isS, curr + j)) {
				issame = false;
				break;
			} else if (j && is_lms(isS, prev + j) && is_lms(isS, curr + j)) {
				break;
			}

			j++;
		}

		if (issame) {
			isunique = false;
		} else {
			num++;
		}
		nums[curr] = num;
	}

	if (!isunique) {
		ull densenums[lmscnt];
		for (i = 0; i < lmscnt; i++) {
			densenums[i] = nums[lms[i]];
		}
		sa_is(densenums, sa, lmscnt - 1, num + 1);
		for (i = 0; i < lmscnt; i++) {
			lmssort[i] = lms[sa[i]];
		}
	}

	induced_sort(s, sa, isS, lmssort, n, lmscnt, ckind);
}

void odd () {
	sll i, j;
	for (i = 0; i < h; i++) {
		for (j = 0; j < w; j++) {
			a[i][j] = (i + j) % 2;
		}
	}
}
bool isvalid (sll i, sll j) {
	if (i < 0 || i >= h || j < 0 || j >= w) return false;
	return true;
}
void even (ull k) {
	sll i, j;

	for (i = 1; i <= 3000; i += 2) {
		for (j = 0; j <= i; j++) {
			sll ri = i - j;

			// ull col1 = (i / k) & 1;
			// ull col2 = ((j + ri * (k - 1)) / (k)) & 1;
			ull col1 = ((ri + j) / k) & 1;
			ull col2 = ((3000 + ri - j) / k) & 1;
			ull colt = col1 * 2 + col2;

			if (isvalid(ri, j - 1)) {
				// a[ri][j - 1] = ((i / k) & 1) * 2 + ((((k / 2) * i + j - i) / (k / 2)) & 1);
				a[ri][j - 1] = colt;
			}
			if (isvalid(ri, j)) {
				// a[ri][j] = ((i / k) & 1) * 2 + ((((k / 2) * i + j - i) / (k / 2)) & 1);
				a[ri][j] = colt;
			}
		}

	}
}

ull solve () {
	sll i, j, ki, li;
	ull result = 0;
	// sll result = 0;
	double dresult = 0;
	// ull maybe = 0;
	sll maybe = 0;
	// ull sum = 0;
	sll sum = 0;
	sll item;
	ull *dpcell;

	if (q & 1) {
		odd();
	} else {
		even(q);
	}

	for (i = 0; i < h; i++) {
		for (j = 0; j < w; j++) {
			putchar("RYGB"[a[i][j]]);
		}
		puts("");
	}

	// printf("%lld\n", result);
	// printf("%.15lf\n", dresult);
	// puts(s);

	return 0;

	success:
	// puts("YES");
	puts("Yes");
	// printf("%llu\n", result);
	// puts("0");
	// puts("Yay!");
	return 0;

	fail:
	// puts("NO");
	puts("No");
	// puts("0");
	// puts("-1");
	// puts("-1 -1 -1");
	// puts(":(");
	return 1;
}

int32_t main (void) {
	int32_t i, j;
	int32_t x, y;

	// scanf("%llu%llu", &n, &m);
	// scanf("%llu", &k, &n, &m);
	scanf("%llu%llu", &h, &w);
	// scanf("%lld", &va, &vb, &vc, &vd);
	// scanf("%llu%llu", &ua, &ub, &uc, &ud);
	scanf("%llu", &q);
	// scanf("%s", s);
	// scanf("%s", t);
	// for (i = 0; i < n; i++) {
	// 	// scanf("%lld%lld", &xy[i].a, &xy[i].b);
	// 	scanf("%lld", &a[i]);
	// 	// scanf("%lld", &b[i]);
	// 	// scanf("%lld", &c[i]);
	// 	// scanf("%lld", &d[i]);
	// 	// a[i]--;
	// 	// b[i]--;
	// 	// c[i]--;
	// }
	// scanf("%llu", &m, &k);
	// scanf("%llu", &q);
	// for (i = 0; i < n; i++) {
	// 	scanf("%lld", &b[i]);
	// }

	// for (i = 0; i < n; i++) {
	// 	for (j = 0; j < n; j++) {
	// 		scanf("%llu", &table[i][j]);
	// 	}
	// }
	// for (i = 0; i < h; i++) {
	// 	scanf("%s", &s[i]);
	// }

	solve();

	return 0;
}