@Test
	public void resolve() {
		int N=20;
		long [][] grid=new long[N+1][N+1];
		for(int i=N;i>=0;i--){
			for(int j=N;j>=0;j--){
				if(i==N||j==N){
					grid[i][j]=1;
				}else{
					grid[i][j]=grid[i][j+1]+grid[i+1][j];
				}
			}
		}
		print(grid[0][0]);
	}