app.py

import streamlit as st
st.title('Welcome to the BMI Calculator')

weight = st.number_input("Enter your weight in Kgs")
status = st.radio("Select your height format",("cms","meters","feet"))

try:
    if status == "cms":
        height = st.number_input('Centimeters')
        bmi = weight/((height/100)**2)

    elif status == "meters":
        height = st.number_input('meters')
        bmi = weight/((height)**2)
    else:
        height = st.number_input('feet')
        bmi = weight/((height/3.28)**2)
except:
    print('Zero division Error')

if (st.button('Calculate BMI')):
    st.write("Your BMI index is {}.".format(round(bmi)))
    if bmi < 16:
        st.error('You are extremely underweight')
    elif (bmi>=16 and bmi<18.5):
        st.warning('You are underweight')
    elif (bmi>=18.5 and bmi<25):
        st.success('You are Healthy')
    elif (bmi>=25 and bmi<30):
        st.warning('You are Overweight')
    else:
        st.error('extremely Overweight')