Ositus

def noOverlaps(a,b):
    for i in range(len(a)):
        if b.find(a[i])!=-1:
            return False
    return True

# U=input()
#I="aybabtu"
# ends={0:1}
# for i in range(len(I)):
    # s=I[i]
    # newEnds={i:0}
    # k=i
    # while k!=-1:
    #     newEnds[i]+=ends[k]
    #     if s==I[k]:
    #         k=-1
    #     else:
    #         sortEnd=k
    #         newEnds.setdefault(sortEnd,0)
    #         newEnds[sortEnd]+=ends[k]
    #         k-=1
    # ends=newEnds
    # print(ends)

# ends={}
# for i in range(len(I)):
#     print(i)
#     s=I[i]
#     cut = I.rfind(s,0,i)
#     newEnds={i:0}
#     for j in range(i):
#         if j>cut:
#             newEnds[j] = ends[j]
#         newEnds[i] +=ends[j]
    
#     ends=newEnds
#     print(ends)

# I="aybabtu"
I=input()
ends={0:1}
for i in range(1,len(I)):
    s=I[i]
    newEnds={i:0}
    for k in ends.keys():
        if I.find(s,k,i)==-1:
            sortEnd=k
            newEnds.setdefault(sortEnd,0)
            newEnds[sortEnd]+=ends[k]
        newEnds[i]+=ends[k]
    ends=newEnds
    # print(ends)



total=0
for k in ends.keys():
    total+=ends[k]
print(total%(7+(10**9)))

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

Test 5

Group: 2, 3

Verdict: ACCEPTED

Test 6

Group: 3

Verdict: ACCEPTED

Test 7

Group: 3

Verdict: TIME LIMIT EXCEEDED