Can anybody tell me what’s wrong with my code? I have been trying this problem for weeks but still no result. I am getting correct ouput for all testcases and my custom testcases but when I submit it shows NZEC runtime error. Help me please!!!
# cook your dish here
def prec(op):
if op=='*' or op=='/':
return 2
elif op=='+' or op=='-':
return 1
elif op=='^':
return 3
t=int(input())
while t>0:
n=int(input())
s=input()
st=[]
for ch in s:
if ch.isalpha():
print(ch,end='')
elif ch==')':
while len(st)!=0:
if st[-1]=='(':
st.pop()
break
print(st.pop(),end='')
elif ch=='(' or len(st)==0 or st[-1]=='(' or prec(st[-1])<prec(ch):
st.append(ch)
else:
while len(st)!=0:
if st[-1]=='(':
break
elif prec(st[-1])>=prec(ch):
print(st.pop(),end='')
else:
break
st.append(ch)
while len(st)!=0:
print(st.pop(),end='')
print()
t=t-1