JavaScript solution, faster than 97.78%
\nvar maxPower = function(s) {\n    let maxStr = 1;\n    let accum = 0;\n    for (let i = 0; i < s.length; i++) {\n        if (s[i] === s[i + 1]) {\n           
```\nvar maxPower = function(s) {\n    let maxStr = 1;\n    let accum = 0;\n    for (let i = 0; i < s.length; i++) {\n        if (s[i] === s[i + 1]) {\n            maxStr += 1;\n        } else {\n            maxStr = 1;\n        }\n        if (maxStr > accum) {\n            accum = maxStr;\n        }\n    }\n\n    return accum;\n};\n```
['JavaScript']