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???????????????????????Java?????????????????

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public static void Fa() {    Scanner sr = new Scanner(System.in);    int s = sr.nextInt();    String str = "";    while (s >= 8) {        str += s % 8;        s = s / 8;    }    str = str + s;    StringBuffer sb = new StringBuffer(str);    System.out.println(sb.reverse());}

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Java???Integer.toOctalString(int)??????????????????????

public static void Fb() {    Scanner sr = new Scanner(System.in);    int a = sr.nextInt();    if (0 <= a && a <= 2147483647) {        System.out.println(Integer.toOctalString(a));    }}

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???????????????0?15???????10?15????????A?F?

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public static void Za() {    Scanner sr = new Scanner(System.in);    int s = sr.nextInt();    String str = "";    while (s >= 16) {        str += s % 16;        s = s / 16;    }    switch (str) {        case "10": str += "A"; break;        case "11": str += "B"; break;        case "12": str += "C"; break;        case "13": str += "D"; break;        case "14": str += "E"; break;        case "15": str += "F"; break;        default: str = s + str; break;    }    System.out.println(str);}

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Java?Integer.toHexString(int)??????????????????????????????????toUpperCase()????????

public static void Zb() {    Scanner sr = new Scanner(System.in);    int a = sr.nextInt();    if (0 <= a && a <= 2147483647) {        String b = Integer.toHexString(a).toUpperCase();        System.out.println(b);    }}

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public static void main(String[] args) {    Scanner sr = new Scanner(System.in);    int a = sr.nextInt();    System.out.println(Integer.toOctalString(a));}

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public static void main(String[] args) {    Scanner sr = new Scanner(System.in);    String a16 = sr.next();    char[] b16 = a16.toCharArray();    int a10 = 0;    for (int i = 0; i < b16.length; i++) {        a10 += xia(b16[i]) * Math.pow(16, b16.length - 1 - i);    }    System.out.println(a10);}public static int xia(int ace) {    char[] wt = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };    for (int i = 0; i < wt.length; i++) {        if (wt[i] == ace) {            return i;        }    }    return -1;}

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