Javascript, 109 104 100 98 bytes

function c(s){q=l={};s.split('').map(function(k){q[k]=Math.max(n=k==l?n+1:1,q[l=k]|0)});return q} 

Example usage:

console.log(c("aaaaaddfffabbbbdb")) 

outputs:

{ a: 5, d: 2, f: 3, b: 4 } 

PHP, 104 102 96

<?php function _($s){while($n=$s[$i++]){$a[$n]=max($a[$n],$n!=$s[$i-2]?$v=1:++$v);}print_r($a);} 

usage

_('asdaaaadddscc'); 

printed

Array ( [a] => 4 [s] => 1 [d] => 3 [c] => 2 ) 

Java 247

import java.util.*;public class a{public static void main(String[]a){Map<Character, Integer> m = new HashMap<>();for(char c:a[0].toCharArray()){Integer v=m.get(c);m.put(c,v==null?1:v+1);}for(char c:m.keySet())System.out.println(c+"="+m.get(c));}} 

C 169

Iterates each printable character in ASCII table and counts max from input string.

#define N 128 int c,i,n; char Y[N],*p; int main(){gets(Y); for(c=33;c<127;c++){p=Y;n=0,i=0;while(*p){if(*p==c){i++;}else{n=(i>n)?i:n;i=0;}p++;} if(n>0) printf("%c=%d\n",c,n);} } 

JavaScript 116

prompt(x={}).replace(/(.)\1*/g,function(m,l){n=m.length if(!x[l]||x[l]<n)x[l]=n}) for(k in x)console.log(k+'='+x[k]) 

Groovy - 80 chars

Based on this clever answer by xnor :

t=args[0];t.toSet().each{i=0; while(t.contains(it*++i)); println "${it}=${i-1}"} 

Output:

$ groovy Golf.groovy abbcccdddd d=4 b=2 c=3 a=1 

Ungolfed:

t=args[0] t.toSet().each { c -> i=0 s=c // repeat the char c with length i // e.g. "b", "bb", "bbb", etc // stop when we find a length that is not in t: // this is the max + 1 while (t.contains(s)) { i++ s=c*i } println "${c}=${i-1}" } 

Javascript (E6) 103

A javascript solution that cares about the requested output format.

F=a=>(p=q={},m={},[...a].map(x=>(x!=p&&(q[p=x]=0),m[x]>++q[x]?0:m[x]=q[x])),''+[i+'='+m[i]for(i in m)]) 

Ungolfed

F=a=>( p=q={}, m={}, [...a].map( x=>( x!=p && (q[p=x]=0), m[x] > ++q[x] ? 0 : m[x] = q[x] ) ), '' + [i+'='+m[i] for(i in m)] ) 

Test

In Firefox console

console.log(F("aaaaaddfffabbbbdb")) 

a=5,d=2,f=3,b=4

R (219, 213, 197, 196, 191, 165, 169, 157, 163 characters)

The data.table version added. There was an error in the previous data.table version.

Golfed data.table version (163)

require(data.table);f=function(x){x=strsplit(x,"")[[1]];data.table(x=x,y=cumsum(c(1,x[-1]!=head(x,-1))))[,.N,list(x,y)][order(-N)][!duplicated(x),paste0(x,"=",N)]} 

Ungolfed data.table version

require(data.table) f <- function(x) { x <- strsplit(x, "")[[1]] data.table(a=x, y=cumsum(c(1, x[-1] != head(x, -1))))[ , .N, list(a, y)][order(-N)][!duplicated(a), paste0(a, "=", N)] } 

Golfed data.frame version (174)

f=function(x){x=strsplit(x,"")[[1]];d=data.frame(a=x,y=cumsum(c(1,x[-1]!=head(x,-1))));d=aggregate(d$y,d,length);d=d[order(-d$x),];d=d[!duplicated(d$a),];paste0(d$a,"=",d$x)} 

Ungolfed data.frame version

f <- function(x) { x <- strsplit(x, "")[[1]] d <- data.frame(a = x, y = cumsum(c(1, x[-1] != head(x, -1)))) d <- aggregate(d$y, d, length) d <- d[order(-d$x), ] d <- d[!duplicated(d$a), ] paste0(d$a, "=", d$x) } f("acbaabbbaaaaacc") f("acbaabbbaaaaaccdee") 

It's written in Python, in order to run the code, just call thefunction maxsequence(str). For instance, maxsequence('aaaaaannndmdejlsfnsfsssssnnnnnxxx') or maxsequence("kdkdkdkdjeeeiwwwnnnmdnnsbjdiiiiiiiiiidndbbcbbccbcvcvdddcjdjdjwwwwwwkkkkxlxllllllll")

def maxsequence(str): count = 1 # count if the letters are repeat step = 0 # once the next letter changed, step = count. countArray = [] # put all the sequence numbers in an array lettersArray = [] # put all the repeat letters in an array max = 0 # for calculating the max of the array, it needs two indexes to do that indexFirst = 0 indexNext = 1 i = 0 while(i<len(str) and i<=(len(str)-2)): if(str[i]==str[i+1]): count += 1 step = count else: lettersArray.append(str[i]) step = count countArray.append(step) count = 1 i += 1 countArray.append(step) lettersArray.append(str[i]) while(countArray[indexFirst]>=countArray[indexNext] and indexNext<(len(countArray)-1)): indexNext += 1 if(countArray[indexFirst]<=countArray[indexNext]): indexFirst = indexNext max = countArray[indexFirst] for i in range(len(lettersArray)): print lettersArray[i],"=",countArray[i] print "The max sequence is:", max return max 

Scala – 99 as program, 97 as function

Program (reads one line from stdin)

for((k,v)<-"(.)\\1*".r.findAllIn(Console.in.readLine).toSeq.groupBy(_(0)))println(k+"="+v.max.size) 

Function:

def f(s:String)=for((k,v)<-"(.)\\1*".r.findAllIn(s).toSeq.groupBy(_(0)))println(k+"="+v.max.size) 

Clojure - 105 bytes

I'm learning Clojure at the moment and what would be a better way to do it than golfing? So, here's my second entry to this challenge.

(def f #(apply str(for[c(distinct %)](str c\=(apply max(map count(re-seq(re-pattern(str c\+))%)))"\n")))) 

Examples:

=> (f "acbaabbbaaaaacc") "a=5\nc=2\nb=3\n" => (f "aaaabaa") "a=4\nb=1\n" => (println (f "acbaabbbaaaaacc")) a=5 c=2 b=3 

J 45

~.,.'=',.":@({.@>>.//.$&>)@(<;.2~2&(~:/\),1:) 

As a verb. Though for using it , you'd need to assign it to a name, eg:

f=:~.,.'=',.":@({.@>>.//.$&>)@(<;.2~2&(~:/\),1:) f 'acbaabbbaaaaacc' a=5 c=2 b=3 

Short explanation:

 @( 2&(~:/\),1:): find where neighbors are different <;.2~ : cut in these places ( $&> ) : get the length of the string in the box ({.@>) : get the first letter from the box (>./)/. : get the maximum for each unique char ~.,.'=',.":@( ) : Output: letter = stringified value 

BACCHUS, 41

'acbaabbbaaaaacc'j:A=·z#:B=($A,$0h:a(·>0.$0,'=',·+)?),$B¨n 

I have discounted the actual parameter String.

Explanation

j:A= Transform the String in a block (some sort of array) and stores it in A variable.

·z#:B= Read last value on the stack (the block) and removes al duplicates, storing it in B.

( Open for each

$A,$0h:a counts how many times the current element of the for each is present in A (read as a String) and pushes this value to Stack (this avoid inmediate printing of the value).

( Open if

·>0. is last value is > 0 then

$0,'=',·+ Concatenates current for each element, '=' and last value in stack (that will be printed out)

)? Close if

,$B¨ Close for each indicating the block to loop over (B).

n Indicates that the output must be space separated

Python 3, 88 bytes

from re import*;a=input();[(i[0],len(max(i))) for i in(findall(l+"+",a)for l in set(a))] 

Outputs in a format of:

[('b', 3), ('c', 2), ('a', 5)] 

Clojure, 107 bytes

#(apply str(for[p(vals(group-by last(partition-by(fn[i]i)%)))](str(ffirst p)\=(apply max(map count p))\,))) 

Returns "a=5,c=2,b=3," for the example input. This would have been 89 bytes, returning ([\a 5] [\c 2] [\b 3]):

#(for[p(vals(group-by last(partition-by(fn[i]i)%)))][(ffirst p)(apply max(map count p))]) 

APL (Dyalog), 41 bytes

{(⊃,'=',⍕∘≢)¨l[∪⍳⍨⊃¨l←n[⍒≢¨n←⍵⊂⍨1,2≠/⍵]]} 

Try it online!

Ungolfed:

{ n←⍵⊂⍨1,2≠/⍵ l←n[⍒≢¨n] (⊃,'=',⍕∘≢)¨l[∪⍳⍨⊃¨l] } 

{ anonymous function

 2≠/⍵ pair-wise sliding window inequality of the argument
 1, prepend a one
 ⍵⊂⍨ use that to partition the argument
 n← store in n

 n[…] index n with:
  ⍒ the descending order of
  ≢¨ the length of each element in
  ⍵ argument
 l← store in l

 l[…] index l with:
  ∪ the unique of
  ⍳⍨ the first occurrence of each element of
  ⊃¨l the first element of each of l
 (…)¨ apply the following tacit function on each element
  ⊃ the first element
  , concatenated to
  '=' an equal sign
  , concatenated to
  ⍕∘≢ the formatted length

}

Java, 192 bytes

import java.util.*;s->{int p=0,c=0;Map<Character,Integer>m=new HashMap();for(byte b:s.getBytes()){c=p==b?c+1:1;m.merge((char)(p=b),c,Math::max);}m.forEach((k,v)->System.out.println(k+"="+v));} 

Try it online!

Java, 251 bytes (with regular expressions)

import java.util.regex.*;import java.util.function.*;s->{Matcher m=Pattern.compile("(.)\\1*").matcher(s);Map<String,Integer>a=new HashMap();while(m.find())a.merge(m.group(1),m.group().length(),Math::max);a.forEach((k,v)->System.out.println(k+'='+v));} 

Try it online!

Java Code: Out of interest I just found a solution will further enhance soon.

import java.util.HashMap; 

import java.util.Map.Entry; import java.util.Scanner;

public class MaxSequenceLength { private HashMap characterCount = new HashMap<>();

public static void main(String[] args) { Scanner inputScanner = new Scanner(System.in); new MaxSequenceLength().validateInput(inputScanner.nextLine()); inputScanner.close(); } private void validateInput(String inputString) { if (inputString.length() <= 1024) { scanInput(inputString.toCharArray()); } } private void scanInput(char[] characterArrayInput) { for (char tempCharacter : characterArrayInput) { if ((int) tempCharacter < 65 || ((int) tempCharacter > 90 && (int) tempCharacter < 97) || (int) tempCharacter > 122) { continue; } else if (characterCount.containsKey(tempCharacter)) { characterCount.put(tempCharacter, characterCount.get(tempCharacter) + 1); } else { characterCount.put(tempCharacter, 1); } } for (Entry<Character, Integer> tempEntry : characterCount.entrySet()) { System.out.println(tempEntry.getKey() + " = " + tempEntry.getValue()); } } 

}

The code would ignore all the other symbols and give only case sensitive character output.

Python (62 55)

n=raw_input() print map(lambda x:[x,n.count(x)],set(n)) 

Old answer:

n=raw_input() s=set(n) print zip(s,map(lambda x:[x,n.count(x)],s))