This is the program to find divisor of two numbers but the answer of any number I input comes out to be 1. Where am I going wrong?

```
def divisor(a,b):
result=1
for i in range(b,-1):
if a%i==0 and b%i==0:
result=i
break
return result
num=input("calculate HCF of: ").split(",")
print(divisor(int(num[0]),int(num[1])))
```

Source: Python Questions