# Problem of the DayA new programming or logic puzzle every Mon-Fri

## Minify Sum

Happy Monday!

Today's problem involves turning a long number in to a short number. The goal is to sum each digit of the number recursively until you reach a single digit. Here are a few test cases to make it easier to understand.

```123456 = 1+2+3+4+5+6 = 2+1 = 3

99 = 9+9 = 1+8 = 9
```

• - 8 years ago

Run with node with the argument being after the filename ``` \$: node app.js 123456 ```

``````var input = 999;

if(process.argv[2]){
input = process.argv[2];
}

console.log(minify(input));

function minify (input)
{
var sum = 0;
input.toString().split("").forEach(function (value){
sum += parseInt(value);
});
if (sum > 9){
return minify(sum);
}
return sum;
}
``````
• Anonymous - 8 years ago

``````#python
def minify(number):
minifiedsum = 0
while number > 0:

minifiedsum = minifiedsum + number % 10
number = number/10

if minifiedsum > 9:
return minify(minifiedsum)
else:
return minifiedsum
``````
• Anonymous - 8 years ago

``````def minify_sum(n):
return minify_sum(sum(map(int, str(n)))) if n > 9 else n
``````

Content curated by @MaxBurstein