java编程：根据EXCEL列名求其索引

原理：

[a1-z26]*26^n-1 + [a1-z26]*26^n-2 + ... + [a1-z26]*26^0

/*
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import java.util.HashMap;
import java.util.Map;

/**
 *
 * @author jdkleo
 */
public class ExcelUtil {

    public static int getCellNum(String cellStr) {
        char[] cellStrArray = cellStr.toUpperCase().toCharArray();
        int len = cellStrArray.length;
        int n = 0;
        for(int i=0;i<len;i++){
            n += (((int)cellStrArray[i])-65+1)*Math.pow(26, len-i-1);
        }
        return n-1;
    }

    public static void main(String[] args) {
        System.out.print(getCellNum("aaa"));
    }
}