Python - 'int' object is not subscriptable with dictionary

I'm trying to do a comparison to see if I can continue with a certain function, but I get the 'int' object is not subscriptable.

sect is a dictionary with 4 keys, each key is a list with either 30 or 49 indexes. I just want to check if a certain index minus a number will be more or less than 0.

import time
from collections import defaultdict

def getFile(fn):
    fn = open(fn, 'r')
    numArr = [line.split()for line in fn]
    fn.close()
    return numArr

trans = getFile("transactions.txt")


def dictindict(rows, seats):
    sections = defaultdict(list)

for key in range(0, 4):
    for j in range(1, rows):
        sections[key].append(seats)
return sections

tSeats = 96
eSeats = 196
sSeats = 96

tSect = dictindict(40, 96)
eSect = dictindict(50, 196)
sSect = dictindict(50, 96)


def buyTix(trans, sect, sC, rC):
    numTix = int(trans[3])
    print(sect)
    if (sect[sC][rC] - numTix) >= 0: # SELLS THE TICKETS
        sect[sC][rC] -= numTix
        return sect[sC][rC]
    elif (sect[sC][rC] - numTix) < 0 and rC < len(sect[sC]): # CHECK IF ROW IS FULL
        return buyTix(trans, sect, sC, rC + 1)
    elif (sect[sC][rC] - numTix) < 0 and rC == len(sect[sC]): # CHECK IF SECTION FULL
        return buyTix(trans, sect, sC + 1, 


for i in range(0, 5):
    if trans[i][0] == "BUY":
        if trans[i][2] == "E":
            eSect = buyTix(trans[i], eSect, 0, 0)
        elif trans[i][2] == "T":
            tSect = buyTix(trans[i], tSect, 0, 0)
        elif trans[i][2] == "S":
            sSect = buyTix(trans[i], sSect, 0, 0)

sC and rC are just counters that start at 0.

Thanks.