東京大学大学院情報理工学系研究科創造情報学専攻の2016年度実技試験（プログラミング）の解答例（Python3）です。
https://www.i.u-tokyo.ac.jp/common/file/edu/course/ci/2015-8-program.pdf

※公開元ページはこちら
※記載の内容は筆者が個人的に解いたものであり、正答を保証するものではなく、また東京大学及び本試験内容の提供に関わる組織とは無関係です。

#(1)

mport sys
  
a = sys.argv[1]
l = len(a)
i = 1

s = 0
for c in range(l):
    n=4**(l-i)*int(a[c])
    #print(n)
    s=s+n
    i=i+1
print(s)

#(2)

import sys

a = sys.argv[1]
l = len(a)
i = 1

ds = {'a':0,'b':1,'c':2,'d':3,'e':4,'f':5,'g':6,'h':7}
s = 0
for c in range(l):
    n=len(ds)**(l-i)*int(ds[a[c]])
    #print(n)
    s=s+n
    i=i+1
print(s)

#(3)

import sys
  
a = sys.argv[1]
r = {'I':1,'IV':4,'V':5,'IX':9,'X':10,'XL':40,'L':50,'XC':90,'C':100,'CD':400,'D':500,'CM':900,'M':1000}

def putChars(n, cs=""):
    for k, v in sorted(r.items(), key=lambda x: -x[1]):
        if (v<=n):
            cs = cs + k
            if (n-v==0):
                return cs
            else:
                return putChars(n-v,cs)
            break

ret=putChars(int(a))
print(ret)

#(4)

import sys

a = sys.argv[1]
l = len(a)
r = {'I':1,'IV':4,'V':5,'IX':9,'X':10,'XL':40,'L':50,'XC':90,'C':100,'CD':400,'D':500,'CM':900,'M':1000}
sum = 0
c = 0
while(1):
    try:
        n1 = r[a[c]]
        n2 = r[a[c+1]]
        n3 = r[a[c+2]]
        if (n1>n2 and n3>n2):
            nx = n1-n2+n3
            sum = sum + nx
            c = c + 3
            if (c>=len(a)):
                break
            else:
                continue
    except IndexError:
        try:
            n1 = r[a[c]]
            n2 = r[a[c+1]]
            if (n2>n1):
                nx = n2-n1
                sum = sum + nx
                c = c + 2
                if (c>=len(a)):
                    break
                else:
                    continue
        except IndexError:
            pass

    try:
        ps = a[c] + a[c+1]
    except IndexError:
        ps = a[c]
    try:
        r[ps]
        c = c + 1
    except KeyError:
        ps = a[c]
    sum = sum + r[ps]
    c = c + 1
    if (c>=len(a)):
        break
print(sum)

#(5)
(3)と同じなため省略。

#(6)
(4)と同じなため省略

#(7)

import sys
  
a = sys.argv[1]
a = a.split(' ')
l = len(a)
ds = {'one':1,'two':2,'three':3,'four':4,'five':5,'six':6,'seven':7,'eight':8,'nine':9,'ten':10,'eleven':11,'twelve':12,'thirteen':13,'fourteen':14,'fifteen':15,'sixteen':16,'seventeen':17,'eighteen':18,'nineteen':19,'twenty':20,'thirty':30,'fourty':40,'fifty':50,'sixty':60,'seventy':70,'eighty':80,'ninety':90,'hundred':100,'thousand':1000}

def getUpper(si):
    i = si-1
    while(1):
        if (i<0 or ds[a[i]]>ds[a[si]]):
            break
        i = i -1
    return i+1

def calcPartial(si, ei):
    if (si==ei):
        return ds[a[si]]
    else:
        i = si - 1
        sum = 0
        while(1):
            sum = sum + ds[a[i]]
            if (i==ei):
                break
            i = i - 1
        return sum*ds[a[si]]

sum = 0
c = l-1
while(1):
    gu = getUpper(c)
    cp = calcPartial(c,gu)
    c = gu - 1
    sum = sum + cp
    if (c<0):
        break
print(sum)