import std; void main() { int D; readf("%d\n", D); auto a = readln.chomp.split.to!(int[]); foreach_reverse (i; 3 .. D+1) { a[i-2] += a[i]; a[i] = 0; } int[] b; foreach_reverse (i; 0 .. 3) { if (b.empty && a[i] == 0) { continue; } b ~= a[i]; } if (b.empty) { writeln(0); writeln(0); } else { auto len = b.length; writeln(len-1); foreach_reverse (i, c; b) { if (i == 0) { writeln(c); } else { write(c, " "); } } } }