1472. Design Browser History

Signed-off-by: rajput-hemant <[email protected]>

Author: rajput-hemant

src/1401-1500/1472 - Design Browser History/design_browser_history.go

@@ -0,0 +1,50 @@
+package main
+
+type BrowserHistory struct {
+	histories   []string
+	currentPage int
+}
+
+func Constructor(homepage string) BrowserHistory {
+	return BrowserHistory{
+		histories:   []string{homepage},
+		currentPage: 0,
+	}
+}
+
+func (this *BrowserHistory) Visit(url string) {
+	if this.currentPage != len(this.histories)-1 {
+		this.histories = append(this.histories[:this.currentPage+1], []string{}...)
+	}
+
+	this.histories = append(this.histories, url)
+	this.currentPage++
+}
+
+func (this *BrowserHistory) Back(steps int) string {
+	for i := this.currentPage; 0 <= i; i-- {
+		if steps == 0 || this.currentPage == 0 {
+			break
+		}
+
+		this.currentPage--
+		steps--
+	}
+
+	return this.histories[this.currentPage]
+}
+
+func (this *BrowserHistory) Forward(steps int) string {
+	lenHistories := len(this.histories)
+
+	for i := this.currentPage; i < lenHistories; i++ {
+		if steps == 0 || this.currentPage == lenHistories-1 {
+			break
+		}
+
+		this.currentPage++
+		steps--
+	}
+
+	return this.histories[this.currentPage]
+}