1부터 10000사이에 8 몇 개 있는지??

오래전에 작성한거라….

수정할 부분 알려주세요.

snippet.java

import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
 
public class _2012_06_30_googleInterview {
 
	public static void main(String[] args) {
		int usedCount = getUsedCount(1,       // Range Start Number
						10000,  // Range Last Number 
						8);     // Detecting Number
		System.out.println(String.format("Count : %d", usedCount)); 
	}
 
	private static int getUsedCount(int rangeStartNum, int rangeLastNum, int detectNum) {
		Pattern p =Pattern.compile(Integer.toString(detectNum));
 
		int usedCount = 0;
 
		for (int targetNum = rangeStartNum; targetNum <= rangeLastNum; targetNum++) {
			Matcher m =p.matcher(Integer.toString(targetNum));
			int foundMatchCount =getMatchCount(m); 
			usedCount += foundMatchCount;
 
//			if (foundMatchCount != 0) {
//				System.out.println(String.format("Target:[%d]\tDectedNum:[%d]\tGroupCount:[%d]", targetNum, detectNum, usedCount));
//			}
		}		
		return usedCount;
	}
 
	private static int getMatchCount(Matcher m) {
		int matchCount = 0;
		while (m.find()) {				
			matchCount ++;
		}
		return matchCount;
	}
 
}

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