Three_ways_to_search_list

# 4.5 (102) Python code by Ken Adams
# Three methods for searching a list while, for and enumerate
##################################  using a while loop #################################33

sequenceW = ['A','B','C','D']
print("sequenceW")
print(sequenceW)
value_wantedW = "B"
print("Find " + value_wantedW)
def position_while(value_searched, sequenceW):
    print("This is the while function")
    position = 0 # start at he first item on the list
    while position < len(sequenceW): # the while stops when all the list is checked
        if sequenceW[position] == value_searched: # if the value is found
            return position # its position is returned, the return statement closes the function
        position += 1 # if we dont find the value we move on to the next item on the list
    print(str(value_searched) + " is not on the list")# if the while gets to the end the item is not on the list
    return None # the function will return none and close

the_place= position_while(value_wantedW,sequenceW)
print(value_wantedW +" is at position " + str(the_place))

####################################
print("\n")
sequenceF = ['A','B','C','D']
print("sequenceF")
print(sequenceF)
value_wantedF = "H"
print("Find " + value_wantedF)
#Example 2 - A for loop over a range; similar code to while
def position_for(value_searched, sequenceF):
    print("This uses a for loop")
    for position in range(len(sequenceF)):
        if sequenceF[position] == value_searched: # if the value is found
            return position
    print(str(value_searched) + " is not on the list")
    return None

the_placeF= position_for(value_wantedF,sequenceF)
print(value_wantedF +" is at position " + str(the_placeF))

################################################## using enumerate
print("\n")
sequenceE = ['A','B','C','D']
print("sequenceE")
print(sequenceE)
value_wantedE = "D"
print("Find " + value_wantedE)
#Example 3 - The enumerate function; similar code to while

def position_emum(value_searched, sequenceE):
    print("This is pyhons own enemerate")
    for position, item in enumerate(sequenceE):
        if sequenceE[position] == value_searched:
            return position
    print(str(value_searched) + " is not on the list")
    return None

the_placeE= position_emum(value_wantedE,sequenceE)
print(value_wantedE +" is at position " + str(the_placeE))