Stuck on algorithmic string task in js [closed]

I need help on that string task for a intership program(i have already handed over the tasks),but i really stuck in the start of the task.
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    const arr = ["zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine"];

const getValue = (temp) => {
    for (i = 0; i < 10; i++) {
        if (temp === arr[i]) {
            return i;
        }
    }
    return;
}


const charToDigit = (digit) => {
    let index = digit - 48;
    return arr[index];
}

}
console.log(solve(“fiveplusfive”));