I am trying to write a simple function that will test if a an array is consecutive but for some reason it does not work. This is a small part of an angular JS app if that's relevant.
return function isConsecArray(arr){
var i;
var y = (arr.length);
for (i=0; i < y; i += 1){
if (parseInt(arr[i])+1 !== parseInt(arr[i+1]))
{
return false;
}
}
return true;
When reaching the last element, i.e. i=y-1, it compares arr[i] with arr[i+1], which is undefined. You need to iterate up to arr.length-1, i.e.:
...
for (i=1; i < y-1; i += 1) { / NOTE THE y-1 LIMIT
...
You could write it like this:
function isConsecArray(arr) {
var previous = arr[0];
var i;
var y = (arr.length);
if (y > 1) {
for (i=1; i < y; i += 1) {
if (parseInt(arr[i]) -1 !== parseInt(previous)) {
return false;
}
previous = arr[i];
}
}
return true;
}
JSFiddle: http://jsfiddle.net/dq1kccvk/
