http://tabs.ultimate-guitar.com/0-9/4him/a_strange_way_to_save_the_world_crd.htm
Since the song/version you're referring to is based more on the piano than the guitar, you're going to have to "fake" the melody a bit... hopefully the chords will cover the tune well enough for you to be happy with it. Its always a little tricky to try and "cover" a heavily based piano tune (one with lots of runs & chords, both hands busy) with the guitar, especially just one guitar. I don't know what your skill level is, but maybe for starters just aim for a more simplified version on the guitar.