Stacks

class Stack:
     def __init__(self):
          self.items=[]
          
     def isEmpty(self):
         return self.items==[]

     def push(self,item):
         self.items.append(item)

     def pop(self):
         return self.items.pop()

     def peek(self):
         return self.items[len(self.items)-1]

     def size(self):
         return len(self.items)

s=Stack()
p=Stack()
r=Stack()
f=input("Enter file name:")
file=open(f,"r").read()
sc=0
rc=0
pc=0
for symbol in file:
     if symbol=="[":
          s.push(symbol)
     elif symbol=="]":
          if s.size()>0:
               s.pop()
               sc=+1
               print("All [] matched.")
          else:
               print("Not all [] matched")
     elif symbol=="(":
          r.push(symbol)
     elif symbol==")":
          if r.size()>0:
               r.pop()
               rc=+1
               print("All () matched.")
          else:
               print("Not all () matched")
     elif symbol=="{":
          p.push(symbol)
     elif symbol=="}":
          if p.size()>0:
               p.pop()
               pc=+1
               print("All {} matched.")
          else:
               print("Not all {} matched")
          
print(sc)
print(rc)
print(pc)

Heyy I have this code and its returning this:
Enter file name:test1.py
Not all {} matched
All () matched.
All [] matched.
All [] matched.
All () matched.
All {} matched.
1
1
1

I want
Enter the file name: test1.py
() pairs: 2
{} pairs: 1
[] pairs: 2
All () matched.
Not all {} matched.
All [] matched.

What am I doing wrong? Its not even counting properly.