#-*-coding:utf-8-*-
'''
统计用户输入的字符串中有几个数字
'''
#
numList = ['0','1','2','3','4','5','6','7','8','9']
s = input('请输入字符串:')
count = 0
for i in  s:
    if i in numList:
        count +=1
print(count)