我在运行的每个打印语句结束时都会得到"无"打印。我不完全确定为什么？

Question

def finished_projects(unfinished_projects, completed_projects):
while unfinished_projects:
current_project = unfinished_projects.pop()
print('completing project: ' + current_project)
completed_projects.append(current_project)
def show_completed_projects(completed_projects):
print('nThese projects have been completed:')
for project in completed_projects:
print(project)

unfinished_projects = ['pie-chart', 'bar graph', 'line chart']
completed_projects = []
print(finished_projects(unfinished_projects,completed_projects))
print(show_completed_projects(completed_projects))

Answer 1

当您调用函数时，不要添加打印。只需调用函数即可。

def finished_projects(unfinished_projects, completed_projects):
while unfinished_projects:
current_project = unfinished_projects.pop()
print('completing project: ' + current_project)
completed_projects.append(current_project)
def show_completed_projects(completed_projects):
print('nThese projects have been completed:')
for project in completed_projects:
print(project)

unfinished_projects = ['pie-chart', 'bar graph', 'line chart']
completed_projects = []
finished_projects(unfinished_projects,completed_projects)
show_completed_projects(completed_projects)

如果您退货，则可以使用打印。

Answer 2

这是因为您正在尝试打印两个函数的返回值，这两个函数都是None，请尝试这样做：

finished_projects(unfinished_projects,completed_projects)
show_completed_projects(completed_projects)