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#include <stdbool.h>
#include <stdio.h>

int ch;

int
nextCh(void)
{
    ch = getchar();
    return ch;
}

bool
isSpace(int ch)
{
    return ch == ' ';
}

bool
isDecDigit(int ch)
{
    return ch >= '0' && ch <= '9';
}

bool
isOctDigit(int ch)
{
    return ch >= '0' && ch <= '7';
}

bool
isHexDigit(int ch)
{
    return isDecDigit(ch) || (ch >= 'a' && ch <= 'f') ||
           (ch >= 'A' && ch <= 'F');
}

bool
getUint(unsigned long long *res)
{
    unsigned long long val = 0;

    // state S
    while (ch == 0 || ch == ' ') {
        nextCh();
    }
    if (ch == '0') {
        nextCh();
        // state OT
        if (ch == 'x') {
            nextCh();
            // state HT
            if (isHexDigit(ch)) {
                // state H
                while (isHexDigit(ch)) {
                    if (isDecDigit(ch)) {
                        ch -= '0';
                    } else if (ch >= 'a' && ch <= 'f') {
                        ch -= 'a' - 10;
                    } else if (ch >= 'A' && ch <= 'F') {
                        ch -= 'A' - 10;
                    }
                    val = val * 16 + ch;
                    nextCh();
                }
                *res = val;
                return true;
            } else {
                // state E2
                return false;
            }
        }
        // state O
        while (isOctDigit(ch)) {
            ch -= '0';
            val = val * 8 + ch;
            nextCh();
        }
        *res = val;
        return true;
    } else if (isDecDigit(ch)) {
        // state D
        while (isDecDigit(ch)) {
            ch -= '0';
            val = val * 10 + ch;
            nextCh();
        }
        *res = val;
        return true;
    } else {
        return false;
    }
}

int
main()
{
    unsigned long long val = 0;

    if (getUint(&val)) {
        printf("%llu\n", val);
    } else {
        printf("no unsigned integer\n");
    }
}