First and Follow Function

productions=[]
tempProd=[]
nterminals=[]
extra=[]
first={}

follow={}

# n = int(input("Number of Grammers: "))
# for i in range (0,n):
#     g= input("")
#     a=g[3:].split("|")
#     for j in a:
#         productions.append(g[:3]+j)

# productions=["P->i","P->c","P->nTs","Q->P","Q->aS","Q->bSc","R->b","R->$","S->c","S->Rn","S->$","T->RSq",]
# productions=["E->TX","X->+TX","X->$","T->FY","Y->*FY","Y->$","F->(E)","F->i",]
# productionsFollow=["E->TX","X->+TX","X->$","T->FY","Y->*FY","Y->$","F->(E)","F->i",
productions=["S->(A)","S->$","A->TE","E->&TE","E->$","T->(A)","T->a","T->b","T->c",]
# productions=["X->a","X->$","Y->b","Y->$","Z->c","Z->$","A->XYZ",]
# productions=["X->a","X->$","Y->b","Y->$","Z->c","Z->$","A->XYZ",]
tempProd=["S->(A)","S->$","A->TE","E->&TE","E->$","T->(A)","T->a","T->b","T->c",]


#sort lowercase first
print("Sorting")
productions.sort(key=lambda p: p[3].lower())
[print(i) for i in productions]

print("\nNon Terminals:")
for i in productions:
    if i[0] not in nterminals:
        nterminals.extend(i[0])
[print(i) for i in nterminals]


print("\nInitial Dictionaries:")
for i in range(0,len(nterminals)):
        first[nterminals[i]]=[]
[print(f"{i}:{j}") for i,j in first.items()]

#for terminal symbols
for i in range(0,len(nterminals)):
    for j in range(0,len(productions)):
        if nterminals[i]==productions[j][0]:
            if((productions[j][3].isupper()==False) or productions[j][3]=="$"):
                first[nterminals[i]].extend(productions[j][3])

print("\nAfter appending terminals:")
[print(f"{i}:{j}") for i,j in first.items()]


#List out productions starting with a Non-Terminal
print("productions starting with a Non-Terminal")
[extra.append(i) for i in productions if i[3].isupper()]
[print(i) for i in extra]

for i in range(0,len(extra)):
    for j in extra[i][3:]:
        if j.isupper():
            if '$' in first[j]:
                first[j].remove('$')
                first[extra[i][0]].extend(first[j])
                first[j].extend('$')
            elif '$' not in first[j]:
                first[extra[i][0]].extend(first[j])
                break
        elif j.isupper()==False:
            first[extra[i][0]].extend(j)
            break



#To Uniquely Identify
for i in first.keys():
    first[i]=list(set(first[i]))

print("\nFirst FUnction:")
[print(f"First({i})={j}") for i,j in first.items()]


#--------------------------------FOLLOW FUNCTION-----------------------

print("\n\nInitial Follow Dictionary:")
for i in range(0,len(nterminals)):
        follow[nterminals[i]]=[]
[print(f"{i}:{j}") for i,j in follow.items()]

print("\nNon Terminal:")
for i in nterminals:
        print(i)
print("\nProduction:")
for i in tempProd:
        print(i)


print("Main Follow:")
# for i in range(0,len(tempProd)):     # productions[i]
#     for j in range(0,len(nterminals)):  #nterminals[j]
#         for k in tempProd[i][3:]:
#             if k.isupper():

temp=0
for i in range(0,len(tempProd)):     # productions[i]
    flag=0
    for k in tempProd[i][3:]:
        print(k)
        if k.isupper()==False and flag==1:
           print(k)
           print(temp)
           follow[temp].extend(k)
           break
           #follow[k-1].append(k)
        if k.isupper():
            temp=k
            flag=1
    print("\n")



#To Uniquely Identify
for i in follow.keys():
    follow[i]=list(set(follow[i]))

print("\nFollw FUnction:")
[print(f"First({i})={j}") for i,j in follow.items()]