Adding counts based on flags by dates

Could you please advise some direction on how to achieve the below format? I am at lost thinking solution for this problem. basically where flag is 0, sum it up and add it to the very next value where flag is 1 by date date: date hrs_clock some_flag some_count ================================================= 6/20/2016 1 0 5 6/20/2016 2 0 6 6/20/2016 3 1 4 6/20/2016 4 1 2 6/20/2016 5 0 4 6/20/2016 6 0 6 6/21/2016 1 0 4 6/21/2016 2 0 3 6/21/2016 3 1 7 6/21/2016 4 1 2 6/21/2016 5 0 5 6/21/2016 6 0 4 6/22/2016 1 0 5 6/22/2016 2 0 5 6/22/2016 3 1 3 6/22/2016 4 1 2 6/22/2016 5 0 8 6/22/2016 6 0 4 Result: date hrs_clock some_flag some_count ================================================= 6/20/2016 3 1 15 6/20/2016 4 1 2 6/21/2016 3 1 24 6/21/2016 4 1 2 6/22/2016 3 1 22 6/22/2016 4 1 2 6/22/2016 5 0 8 6/22/2016 6 0 4