#include <bits/stdc++.h>
using namespace std;
char dir[10] = {'I', 'V', 'X', 'L', 'C', 'D', 'M'};
int cnt[10][3];
int ans[10];
void init(){int i;for(i = 1; i < 4; i++){cnt[i][0] = i;}cnt[4][0] = cnt[4][1] = 1;cnt[5][1] = 1;for(i = 6; i < 9; i++){cnt[i][0] = i-5; cnt[i][1] = 1;}cnt[9][0] = cnt[9][2] = 1;
}void gao(int x, int base){for(int i = 0; i < 3; i++){//   cout<<x<<" " << cnt[x][i] <<endl;ans[base+i] += cnt[x][i];}
}int main()
{freopen("preface.in","r",stdin);#ifndef poifreopen("preface.out","w",stdout);#endifinit();int n, i, j, x;cin >> n;for(i = 1; i <= n; i++){x = i;if(x >= 1000){ans[6] += x / 1000;x -= (x/1000)*1000;}if(x >= 100){gao(x/100, 4);x-= (x/100)*100;}if(x >= 10){gao(x/10, 2);x-= x/10*10;}if(x>0){//printf("!!%d\n", x);gao(x, 0);}}for(i = 0 ; i <= 6; i++){if(ans[i]){cout << dir[i] <<" " << ans[i] <<endl;}}return 0;
}

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 1005;
ll dp[N];
int main()
{freopen("subset.in","r",stdin);#ifndef poifreopen("subset.out","w",stdout);#endifint n, i, j, m;cin >> n;dp[0] = 1;m = (n+1)*n/2;if(m&1) {cout << 0 <<endl;return 0;}m/=2;for(i = 1; i <= n; i++){for(j = m; j >= 0; j--){if(dp[j] && i + j <= m)   {dp[j+i] += dp[j];}}}cout << dp[m] / 2<< endl;
}

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N  = 14;
bool vis[N];
char str[N];
int len = 0;
int go(int now, int step){step %= len;return (now - step + len) % len;
}
bool gao(int x){memset(vis, false, sizeof(vis));int tp = x, i, now; len = 0;while(tp){str[len++] = tp%10;if(vis[tp%10])return false;vis[tp%10] = true;tp /= 10;}memset(vis, false, sizeof(vis));now = 0;for(int k = 1; k < len; k++){vis[now] =true;now = go(now, str[now]);if(vis[now])    return false;}now = go(now, str[now]);if(now == 0)    return true;return false;}int main()
{freopen("runround.in","r",stdin);#ifndef poifreopen("runround.out","w",stdout);#endifll n;cin >> n;   n++;for(; ; n++){// cout << n << endl;if(gao(n))  break;}cout <<n <<endl;return 0;}

#include <bits/stdc++.h>
using namespace std;
const int N = 34;
const int M = 104;
bool  ans[N][M], same[N][N];
int n, c, id = 0;
bool on[M], off[M];
int f[N];void gao(int x){int one = 0, tp = x, i;while(tp){one += (tp&1);tp >>= 1;}if(c - one < 0 || ((c - one)&1))    return;// printf("%d\n", x);++id;for(i = 1; i <= n; i++) ans[id][i] = 1;if(x&1) for(i = 1; i <= n; i++) ans[id][i] ^= 1;if(x&2) for(i = 1; i <= n; i += 2) ans[id][i] ^= 1;if(x&4) for(i = 2; i <= n; i+= 2)   ans[id][i] ^= 1;if(x&8) for(i = 1; i <= n; i+= 3)   ans[id][i] ^= 1;//f[id] = id;for(i = 1; i <= n; i++){//  printf("%d %d\n", i, ans[id][i]);if(on[i]&& !ans[id][i]){id --;  return;}if(off[i]&&ans[id][i]){id--;   break;}}}bool mor(int j, int k){int i;for(i = 1; i <= n; i++){if(ans[j][i] > ans[k][i]) return true;if(ans[j][i] < ans[k][i]) return false;}same[j][k] = same[k][j] = true;}
int main()
{freopen("lamps.in","r",stdin);#ifndef poifreopen("lamps.out","w",stdout);#endifint i, j, t;cin >> n >> c;while(cin >> t){if(t == -1) break;on[t] = true;}while(cin>>t){if(t == -1) break;off[t] = true;}int limit = (1<<4);for(i = 0; i < limit; i++){//printf("%d\n", i);
        gao(i);}for(i = 1; i <= id; i++)f[i] = i;for(i = 1; i <= id; i++){for(j = 1; j <= id-i; j++){if(mor(f[j], f[j+1])) swap(f[j], f[j+1]);}}for(i = 1; i <= id; i++){if(same[i][i-1])    continue;for(j = 1; j <= n; j++){printf("%d", ans[f[i]][j]);}printf("\n");}if(id == 0) printf("IMPOSSIBLE\n");return 0;}