// NOTE: it is recommended to use this even if you don't understand the following code.

#include <assert.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>

#define MAXN 100000

int B, G, M, N, R, i;
char *masterpiece[MAXN];

int main() {
    // uncomment the two following lines if you want to read/write from files
    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);

    assert(5 == scanf("%d%d%d%d%d", &N, &M, &R, &G, &B));
    

    bool ans = true;
    for (int i = 0; i < N; ++i) {
        masterpiece[i] = malloc(sizeof(char) * M);
    }

    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < M; ++j) {
            masterpiece[i][j] = 'R';
        }
    }


    // INSERT YOUR CODE HERE
    

    if (ans) {
        printf("YES\n");
        for (int i = 0; i < N; ++i) {
            for (int j = 0; j < M; ++j) {
                printf("%c", masterpiece[i][j]);
            }
            printf("\n");
        }
    } else {
        printf("NO\n");
    }

    return 0;
}