lines = []
print("Paste triangle here:")
while True:
    line = input()
    if line:
        lines.append(line)
    else:
        break
text = ' '.join(lines)
numbers = list(map(int, (list(text.split(" ")))))

noprimelist = []
for s in numbers:
    if s > 1:
        for i in range(2, s):
            if (s % i) == 0:
                noprimelist.append(s)
                break
        else:
            noprimelist.append(0)
    elif s == 1:
        noprimelist.append(s)

rowamount1 = int((((8*(len(noprimelist)) + 1)** 0.5) - 1)//2)

rowlist = []
for a in range(rowamount1):
    b = a + 1
    x = (a*(a + 1))//2
    y = (b*(b +1))//2
    rowlist.append(noprimelist[x:y])

for t in range(len(rowlist)):
    if t == 0 and sum(rowlist[t]) == 0:
        del rowlist[0: len(rowlist)]
        rowlist.append([0])
        break
    if t > 0 and sum(rowlist[t]) == 0:
        del rowlist[t: (len(rowlist))]
        break
    else:
        pass

n = len(rowlist) - 1

if len(rowlist) == 1 and rowlist[0][0] == 0:
    print("Maximum sum: 0")
elif len(rowlist) == 1 and rowlist[0][0] != 0:
    print("Maximum sum:", rowlist[0][0])
else:
    s = 0
    nextrange = range(n, 0, -1)
    for n in nextrange:
        while s < n:
            res1 = rowlist[n][s] + rowlist[n - 1][s]
            res2 = rowlist[n][s + 1] + rowlist[n - 1][s]
            if res1 > res2:
                rowlist[n - 1][s] = res1
            else:
                rowlist[n - 1][s] = res2
            s = s + 1
        s = 0
    print("Maximum sum:", rowlist[0][0])