TEC Exa-Blaster Modem 1

EMBER-2 wants to test the "famous for being famous" effect by artificially inserting a random pop song at the top of multiple radio charts.

"Connect to each radio station and insert Can't (not) get over you by Me2u (file 300) at the beginning of each playlist (file 200) without otherwise changing its contents. A list of phone numbers for the radio stations is available in file 301."
 * This is the first mission using the Tec-Blaster modem, which you will use several times. To dial a phone number, write it digit by digit to the #DIAL register. If the phone number is complete and valid, link 800 will be opened to the host you dialed. To close the link, write -1 to #DIAL. You must do this before starting to dial another phone number. EXAs in the previously dialed host will become unable to leave, but can still function and communicate using the M register.
 * Actually, the harder part of this mission is adding material at the beginning of a file. You may need to copy the file to a temporary one. Good job there's space for two EXAs in each of the nodes.