Streaks of either kind

A strategy wins each trading day with probability $p$, independently. Over 50 trading days, what is the probability of a run of at least 5 consecutive days with the same result, meaning 5 wins in a row or 5 losses in a row? Give the answer for $p = 1/2$ and $p = 0.55$, write an exact algorithm for general $n$ days, run length $k$ and win probability $p$, and state its complexity.