class Replacement:
    def replaceSpace(self, iniString, length):
        # write code here
        url = ""
        for s in iniString[:length]:
            if s == " ":
                url += "%20"
            else:
                url += s
        return url
"""
以下代码不用写,直接提交,测试用例就会全部通过
while True:
    try:
        # a= input().split(',')
        a = input().split(',')
        b= a[0]
        c= int(a[1])
        print(Replacement().replaceSpace(b,c))
    except:
        break
"""