unittest
{
	assert( [ "2", "ip cc" ].parse.expand.solve == "icpc" );
	assert( [ "8", "hmhmnknk uuuuuuuu" ].parse.expand.solve == "humuhumunukunuku" );
	assert( [ "5", "aaaaa aaaaa" ].parse.expand.solve == "aaaaaaaaaa" );
}



import std.conv;
import std.range;
import std.stdio;
import std.typecons;

void main()
{
	stdin.byLineCopy.parse.expand.solve.writeln;
}

auto parse( Range )( Range input )
if( isInputRange!Range && is( ElementType!Range == string ) )
{
	input.popFront;
	auto st = input.front.split.to!( dchar[][] );
	return tuple( st[ 0 ], st[ 1 ] );
}

auto solve( dchar[] s, dchar[] t )
{
	auto ans = new dchar[ s.length + t.length ];
	foreach( i, sc, tc; lockstep( s, t ) )
	{
		ans[ i * 2     ] = sc;
		ans[ i * 2 + 1 ] = tc;
	}
	return ans;
}
