add: 220218 [golang]

2202/220218.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"fmt"
+)
+
+func removeKdigits(num string, k int) (ret string) {
+	stack := make([]int32, 0)
+	for _, v := range num {
+		for k > 0 && len(stack) > 0 && stack[len(stack)-1] > v {
+			stack = stack[:len(stack)-1]
+			k--
+		}
+		stack = append(stack, v)
+	}
+	if k > 0 {
+		stack = stack[:len(stack)-k]
+	}
+	for _, v := range stack {
+		ret += string(v)
+	}
+	for len(ret) > 1 && ret[0] == '0' {
+		ret = ret[1:]
+	}
+	if len(ret) == 0 {
+		return "0"
+	}
+	return
+}
+
+func main() {
+	fmt.Println(removeKdigits("1432219", 3))
+}