Find Longest Occurrence Of Same Number In Array

Using JavaScript, I'm trying to find a way to find the longest occurrence of the same number (in this case, 1) in an array. For instance, here's a sample array: [2,5,3,1,1,1,3,7,9,

Solution 1:

I've modified your function slightly. You need to store the highest streak as a separate variable from the current streak, and overwrite that where necessary in your loop - finally returning that variable at the end of your function.

functionstreak(arr) {
    var i,
        temp,
        streak,
        length = arr.length,
        highestStreak = 0;

    for(i = 0; i < length; i++) {
        // check the value of the current entry against the lastif(temp != '' && temp == arr[i]) {
            // it's a match
            streak++;
        } else {
            // it's not a match, start streak from 1
            streak = 1;
        }

        // set current letter for next time
        temp = arr[i];

        // set the master streak varif(streak > highestStreak) {
            highestStreak = streak;
        }
    }

    return highestStreak;
}

vararray = [2,5,3,1,1,1,3,7,9,6,4,1,1,1,1,1,4,7,2,3,1,1,4,3];

console.log(streak(array)); // 5

And if you want to also track what the value of the highest streak was, define another variable at the start of your function, save the value of it when you save the highest streak, and return it as an array:

// set the master streak varif(streak > highestStreak) {
        highestStreakValue = temp;
        highestStreak = streak;
    }
}

return [highestStreak, highestStreakValue];


vararray = [2,5,3,1,1,1,3,7,9,6,4,'a','a','a','a','a',4,7,2,3,1,1,4,3];
console.log(streak(array)); // [5, "a"]

Demo returning both

Solution 2:

An alternative approach. I'm converting the array to a string. The regular expression has a backrefence, which ensures that only sequences of the same character are matched. Also when exec is used with the g flag, repeated executions will continue from the end of last match, and not from the beginning.

var arr = [2,5,3,1,1,1,3,7,9,6,4,1,1,1,1,1,4,7,2,3,1,1,4,3];
var str = arr.join('');
var regex = /(.)\1*/g;
var match;
var largest = '';

while (match = regex.exec(str)) {
  largest = match[0].length > largest.length ? match[0] : largest;
}

console.log(largest.length);

Solution 3:

Your problems:

• You don't store current streak
• You don't specify when streak is more then older streak

Use this:

functionstreak(arr) {
    var i,
        temp,
        streak = 1,
        maxStreak = 0,
        prevNumber,
        length = arr.length;

    for(i=1; i<length; i++) {
        prevNumber = arr[i-1];
        if (arr[i] == prevNumber) {
            streak += 1;
        } else {
            if(streak > maxStreak) {
                maxStreak = streak;
                streak = 1;
            }
        }
    }
    return maxStreak;
}

Demo

Solution 4:

You will need another two arrays here.

1. Store the distinct numbers from your source array using a loop
2. Make a second set of array which is equal to the length of the first set of array which has the distinct numbers.
3. Make a loop equal to the length of the first set of array and then push the values to the second set of array according to its index.
4. Make a loop again using the second set of array and there you will find the most occurence using the index of the second array
5. Finally, get from the first set of array the number using the index you got from step 4.

I did not make the code for you to try it yourself first since you are asking only for some pointers

Solution 5:

Alternative: use regexp and converting the array to a string.

var arr = [2,5,3,1,1,1,3,7,9,6,4,1,1,1,1,1,4,7,2,3,1,1,4,3];
var str = arr.join('').match(/1+/g);
console.log(process ? process.sort().pop() : "No ocurrences");