Java - 100% time 97% space
\nclass Solution {\n    public int numberOfRounds(String startTime, String finishTime) {\n        byte start_hour = Byte.parseByte(startTime.substring(0,2));\n 
```\nclass Solution {\n    public int numberOfRounds(String startTime, String finishTime) {\n        byte start_hour = Byte.parseByte(startTime.substring(0,2));\n        byte start_min = Byte.parseByte(startTime.substring(3,5));\n        byte end_hour = Byte.parseByte(finishTime.substring(0,2));\n        byte end_min = Byte.parseByte(finishTime.substring(3,5));\n        \n        byte value = (byte)(end_hour*4 + end_min/15 - start_hour*4 - (start_min+14)/15);\n        if (start_hour>end_hour || (start_hour==end_hour && start_min>end_min)){\n            value+=96;\n        }\n        \n        return value<0?0:value;\n    }\n}\n```
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