import java.util.*;
public class i {
	Scanner in=new Scanner(System.in);
	public static void main(String[] args) {
		new i().go();
	}
	private void go() {
		int n=in.nextInt();
		long l=in.nextLong();
		long[][] d=new long[n][n];
		for(int i=0;i<n;i++)for(int j=0;j<n;j++)d[i][j]=in.nextLong();
		if(n==2){
			System.out.printf("%s\n", d[0][1]+d[1][0]==l?"possible":"impossible");
			System.exit(0);
		}
		for(int i=1;i<n;i++){//it's a cycle...assume it starts at 0 with midpoint i
			for(int j=0;j<1<<(n-2);j++)if(Integer.bitCount(j)==(n-2)/2 && j<(j^((1<<(n-2))-1))){
				int[] inn=new int[(n-2)/2],out=new int[n-2-(n-2)/2];
				int inni=0,outi=0;
				for(int k=1;k<n;k++)if(k!=i){//skip the breakpoint
					if(((j>>(k-(k>i?2:1)))&1)==1)inn[inni++]=k;
					else out[outi++]=k;
				}
				HashSet<Long> l1=solve(inn,d,0,i);
				HashSet<Long> l2=solve(out,d,i,0);
				for(long ls:l1)if(l2.contains(l-ls)){
					System.out.println("possible");
					System.exit(0);
				}
			}
		}
		System.out.println("impossible");
	}
	private HashSet<Long> solve(int[] inn, long[][] d,int f,int l) {
		HashSet<Long> r=new HashSet<Long>();
		if(inn.length==0){
			r.add(d[f][l]);
			return r;
		}
		do{
			long ans=0;
			ans+=d[f][inn[0]];
			ans+=d[inn[inn.length-1]][l];
			for(int i=0;i<inn.length-1;i++)ans+=d[inn[i]][inn[i+1]];
			r.add(ans);
		} while(nextPermutation(inn));
		return r;
	}
	public boolean nextPermutation(int[] in){
		for(int i=in.length-2;i>=0;i--)if(in[i]<in[i+1]){
			for(int j=in.length-1;j>i;j--)if(in[j]>in[i]){
				int t=in[i];
				in[i]=in[j];
				in[j]=t;
				break;
			}
			for(int j=i+1;j<in.length-(j-i);j++){
				int t=in[j];
				in[j]=in[in.length-(j-i)];
				in[in.length-(j-i)]=t;
			}
			return true;
		}
		return false;
	}
}