str_get = input()
# ls1 = ['IV','IX','XL','XC','CD','CM']
# ls2 = [4, 9, 40, 90, 400, 900]
dt1 = {'I': 1, 'V': 5, 'X': 10, 'L': 50, 'C': 100, 'D': 500, 'M': 1000,
'IV': 4, 'IX': 9, 'XL': 40, 'XC': 90, 'CD': 400, 'CM': 900}
dt2 = {'IV': 4, 'IX': 9, 'XL': 40, 'XC': 90, 'CD': 400, 'CM': 900}
dt3 = {'I': 1, 'V': 5, 'X': 10, 'L': 50, 'C': 100, 'D': 500, 'M': 1000}
result = 0
for key in dt2.keys():
if key in str_get:
result+=dt1[key]*str_get.count(key)
str_get = str_get.replace(key, '')
for key in dt3.keys():
if key in str_get:
result+=dt1[key]*str_get.count(key)
str_get = str_get.replace(key, '')
print(result)