const stringNumber = {
'zero': 0,
'one': 1,
'two': 2,
'three': 3,
'four': 4,
'five': 5,
'six': 6,
'seven': 7,
'eight': 8,
'nine': 9,
};
const numberString = {
0: 'zero',
1: 'one',
2: 'two',
3: 'three',
4: 'four',
5: 'five',
6: 'six',
7: 'seven',
8: 'eight',
9: 'nine',
NaN: 'n/a',
};
const averageString = (str) => numberString[Math.floor(
str.split(' ').reduce((acc, cur) => acc + stringNumber[cur], 0)
/ str.split(' ').length
)];
