#include <bits/stdc++.h>
using namespace std;
int n;
long long md(int x1, int y1, int x2, int y2) {
  return abs(x1 - x2) + abs(y1 - y2);
}
int can(int x, int y, long long t1, long long t2, long long t3, long long t4,
        int a, int b, int c) {
  long long d1, d2, d3, d4, tmp1, tmp2, tmp3, tmp4, tmp5, remain, remainx,
      remainy, tmp;
  int x1, y1, x2, y2, x3, y3, x4, y4;
  x1 = a;
  y1 = b;
  x2 = a + c - 1;
  y2 = b;
  x3 = a;
  y3 = b + c - 1;
  x4 = a + c - 1;
  y4 = b + c - 1;
  d1 = md(x, y, x1, y1);
  d2 = md(x, y, x2, y2);
  d3 = md(x, y, x3, y3);
  d4 = md(x, y, x4, y4);
  if (x < a) {
    t1 -= (d1 - 1 + d1 - (a - x)) * (a - x) / 2;
    d1 -= (a - x);
    t2 -= (d2 - 1 + d2 - (a - x)) * (a - x) / 2;
    d2 -= (a - x);
    t3 -= (d3 - 1 + d3 - (a - x)) * (a - x) / 2;
    d3 -= (a - x);
    t4 -= (d4 - 1 + d4 - (a - x)) * (a - x) / 2;
    d4 -= (a - x);
    x = a;
  }
  if (y < b) {
    t1 -= (d1 - 1 + d1 - (b - y)) * (b - y) / 2;
    d1 -= (b - y);
    t2 -= (d2 - 1 + d2 - (b - y)) * (b - y) / 2;
    d2 -= (b - y);
    t3 -= (d3 - 1 + d3 - (b - y)) * (b - y) / 2;
    d3 -= (b - y);
    t4 -= (d4 - 1 + d4 - (b - y)) * (b - y) / 2;
    d4 -= (b - y);
    y = b;
  }
  remain = n - x + n - y;
  t1 -= (d1 + 1 + d1 + remain) * remain / 2;
  if (t1 < 0) return 0;
  if ((x < (a + c - 1)) && (y < (b + c - 1))) {
    remainx = a + c - 1 - x;
    remainy = b + c - 1 - y;
    tmp1 = (d2 - 1 + d2 - remainx) * remainx / 2 +
           (d2 - remainx + 1 + d2 - remainx + remainy) * remainy / 2;
    tmp2 = (d3 - 1 + d3 - remainy) * remainy / 2 +
           (d3 - remainy + 1 + d3 - remainy + remainx) * remainx / 2;
    tmp3 = (d2 + d3) * (remainx + remainy);
    tmp4 = (t2 + t3 - tmp3) / 2;
    tmp5 = (t2 + t3 - tmp3 + 1) / 2;
    if ((tmp4 - (t2 - tmp1)) % 2 != 0) {
      tmp4--;
      tmp5++;
    }
    if ((t2 - tmp1 >= tmp4) && (t3 - tmp2 >= tmp5)) {
      t2 = tmp4;
      t3 = tmp5;
    } else {
      tmp4 = (t2 + t3 - tmp3 + 1) / 2;
      tmp5 = (t2 + t3 - tmp3) / 2;
      if ((tmp4 - (t2 - tmp1)) % 2 != 0) {
        tmp4++;
        tmp5--;
      }
      if ((t2 - tmp1 >= tmp4) && (t3 - tmp2 >= tmp5)) {
        t2 = tmp4;
        t3 = tmp5;
      } else if (t3 - tmp2 < t2 - tmp1) {
        t3 -= tmp2;
        t2 = tmp4 + tmp5 - t3;
      } else {
        t2 -= tmp1;
        t3 = tmp4 + tmp5 - t2;
      }
    }
    d2 = c - 1;
    d3 = c - 1;
    x = a + c - 1;
    y = b + c - 1;
    t4 -= (d4 - 1 + d4 - remainx - remainy) * (remainx + remainy) / 2;
    d4 -= (remainx + remainy);
  }
  if (x < (a + c - 1)) {
    remain = (a + c - 1) - x;
    t2 -= (d2 - 1 + d2 - remain) * remain / 2;
    d2 -= remain;
    t3 -= (d3 + 1 + d3 + remain) * remain / 2;
    d3 += remain;
    t4 -= (d4 - 1 + d4 - remain) * remain / 2;
    d4 -= remain;
    x = (a + c - 1);
  }
  if (y < (b + c - 1)) {
    remain = (b + c - 1) - y;
    t2 -= (d2 + 1 + d2 + remain) * remain / 2;
    d2 += remain;
    t3 -= (d3 - 1 + d3 - remain) * remain / 2;
    d3 -= remain;
    t4 -= (d4 - 1 + d4 - remain) * remain / 2;
    d4 -= remain;
    y = (b + c - 1);
  }
  remain = n - x + n - y;
  t2 -= (d2 + 1 + d2 + remain) * remain / 2;
  if (t2 < 0) return 0;
  t3 -= (d3 + 1 + d3 + remain) * remain / 2;
  if (t3 < 0) return 0;
  t4 -= (d4 + 1 + d4 + remain) * remain / 2;
  if (t4 < 0) return 0;
  return 1;
}
int main() {
  int a, b, c, x, y;
  int x1, y1, x2, y2, x3, y3, x4, y4;
  long long t, t1, t2, t3, t4;
  scanf("%d%I64d%d%d%d", &n, &t, &a, &b, &c);
  x1 = a;
  y1 = b;
  x2 = a + c - 1;
  y2 = b;
  x3 = a;
  y3 = b + c - 1;
  x4 = a + c - 1;
  y4 = b + c - 1;
  x = 1;
  y = 1;
  if (can(x, y, t, t, t, t, a, b, c) == 0) {
    printf("Impossible\n");
    return 0;
  }
  t1 = t;
  t2 = t;
  t3 = t;
  t4 = t;
  while ((x < n) || (y < n)) {
    if (x < n) {
      if (can(x + 1, y, t1 - md(x + 1, y, x1, y1), t2 - md(x + 1, y, x2, y2),
              t3 - md(x + 1, y, x3, y3), t4 - md(x + 1, y, x4, y4), a, b,
              c) == 1) {
        x++;
        t1 -= md(x, y, x1, y1);
        t2 -= md(x, y, x2, y2);
        t3 -= md(x, y, x3, y3);
        t4 -= md(x, y, x4, y4);
        printf("R");
        continue;
      }
    }
    if (y < n) {
      if (can(x, y + 1, t1 - md(x, y + 1, x1, y1), t2 - md(x, y + 1, x2, y2),
              t3 - md(x, y + 1, x3, y3), t4 - md(x, y + 1, x4, y4), a, b,
              c) == 1) {
        y++;
        t1 -= md(x, y, x1, y1);
        t2 -= md(x, y, x2, y2);
        t3 -= md(x, y, x3, y3);
        t4 -= md(x, y, x4, y4);
        printf("U");
        continue;
      }
    }
    break;
  }
  printf("\n");
  return 0;
}
