#include <cstdio>

using namespace std;

char tmp[10];
int poc1, poc2, raz1, raz2, raz;

int main( void ){
	scanf( "%s", tmp );
	poc1 = tmp[4] - '0' + ( tmp[3] - '0' ) * 10 + ( tmp[1] - '0' + ( tmp[0] - '0' ) * 10 ) * 60;
	scanf( "%s", tmp );
	poc2 = tmp[4] - '0' + ( tmp[3] - '0' ) * 10 + ( tmp[1] - '0' + ( tmp[0] - '0' ) * 10 ) * 60;
	scanf( "%s", tmp );
	raz1 = tmp[4] - '0' + ( tmp[3] - '0' ) * 10 + ( tmp[1] - '0' + ( tmp[0] - '0' ) * 10 ) * 60;
	scanf( "%s", tmp );
	raz2 = tmp[4] - '0' + ( tmp[3] - '0' ) * 10 + ( tmp[1] - '0' + ( tmp[0] - '0' ) * 10 ) * 60;
	raz = ( poc1 % raz1 ) - ( poc2 % raz2 );
	if( raz < 0 ) raz = -raz;
	if( raz1 == raz2 ) {printf( "nikad" ); return 0;}
	bool f = false;
	for( int i = 0; i < raz1; ++i )
		if( ( raz2 * i - raz ) % raz1 == 0 ) f = true;
	if( !f ) {printf( "nikad" ); return 0;}
	int i;
	for( i = poc1 + raz1; ( i - poc2 ) % raz2 != 0; i += raz1 );
	switch( ( ( i - i % 1440 ) / 1440 ) % 7 ){
		case 0:
			printf( "subota\n");
			break;
		case 1:
			printf( "nedjelja\n");
			break;
		case 2:
			printf( "ponedjeljak\n");
			break;
		case 3:
			printf( "utorak\n");
			break;
		case 4:
			printf( "srijeda\n");
			break;
		case 5:
			printf( "cetvrtak\n");
			break;
		case 6:
			printf( "petak\n");
			break;
	}
	i = i % 1440;
	int h = i / 60; int m = i % 60;
	if( h < 10 ) printf( "0%d", h ); else printf( "%d", h );
	printf( ":" );
	if( m < 10 ) printf( "0%d", m ); else printf( "%d", m );
	return 0;
}