class BrowserHistory:
    def __init__(self, homepage: str):
        # Initialize with the homepage
        self.history = [homepage]
        self.pos = 0    # Current index
        self.top = 0    # The current 'end' of valid history

    def visit(self, url: str) -> None:
        self.pos += 1
        
        # If we are visiting a new page from the middle of history,
        # we overwrite the next slot.
        if self.pos < len(self.history):
            self.history[self.pos] = url
        else:
            self.history.append(url)
            
        # After a visit, the 'top' is always our current position
        # effectively deleting any forward history.
        self.top = self.pos

    def back(self, steps: int) -> str:
        # Move back, but don't go past index 0
        self.pos = max(0, self.pos - steps)
        return self.history[self.pos]

    def forward(self, steps: int) -> str:
        # Move forward, but don't go past the 'top'
        self.pos = min(self.top, self.pos + steps)
        return self.history[self.pos]


# Your BrowserHistory object will be instantiated and called as such:
# obj = BrowserHistory(homepage)
# obj.visit(url)
# param_2 = obj.back(steps)
# param_3 = obj.forward(steps)