x = 10 
y = 20
z = "20"
zz = 20.15
# บวกเลข
result = x+y
print(type(x))
print(type(y))
print(type(z))
print(result) #30
print(x+int(z)) #con str to int
print(str(x)+z) #con int to str
print(float(z))#con str to float
print(int(zz)) #con float to str