var binary = [1,0,0,1,1,1,0,0,1,0];I have a function which produces a random array of bits. I would like to combine matching elements and return an array stating how many elements were repeated. The above giving the output = [1,2,3,2,1,1].
Are there any features in JavaScript which would allow me to do this? I have tried searching but not really sure how to describe what I want. Thanks.
You could use reduce() method and store last element in one variable.
var binary = [1, 0, 0, 1, 1, 1, 0, 0, 1, 0];
let last = null;
var result = binary.reduce((r, e) => {
if (last == null || last != e) r.push(1);
else r[r.length - 1]++;
last = e;
return r;
}, [])
console.log(result)Try following
var binary = [1,0,0,1,1,1,0,0,1,0];
var result = []; // result array
var value = binary[0]; // initial value
var counter = 1; // counter of the values
// Start the loop with 2nd value
for (var i = 1; i < binary.length; i++) {
// if the value in array is same as stored value, increment counter
if(value === binary[i]) {
counter++;
} else {
/* if the value is different, push the counter in result
** and reset value and counter */
result.push(counter);
value = binary[i];
counter = 1;
}
}
console.log(result);You could check the last element while reducing the array and either push the increased last value or take 1 for concatination.
var binary = [1, 0, 0, 1, 1, 1, 0, 0, 1, 0],
result = binary.reduce((r, v, i, a) => r.concat((a[i - 1] === v && r.pop()) + 1), []);
console.log(result);this is the way that i founded to check that binary in array is continuously repeated or not
var output = [1,0,0,1,1,1,0,0,1,0];
var result = []
var counter = 1;
for(i=0;i<output.length;i++){
if(output[i] === output[i+1])
counter++;
else{
result.push(counter);
counter=1;
}
}
console.log(result)
here is an output [ 1, 2, 3, 2, 1, 1 ] and this code is simple to understand
A bit shorter and slower alternative:
console.log( [1,0,0,1,1,1,0,0,1,0].join('').match(/0+|1+/g).map(m => m.length) )