'''

```
sum=0
power=0
for i in s[::-1]: # reverse the string
sum+=((ord(i)-64)*(26**power))
power+=1
return sum
```

'''

Because A is 65 in Ascii, you can find column number by subtracting 64,

So A=1 ... Z=26. Each position moves up by a power of 26. (like hex instead of base 16 its base 26)