【HDOJ】1717 小数化分数2

简单字符串处理。

#include <cstdio>
#include <cstring>
#include <cmath>
#include <ctype.h>

#define MAXN 25
char str[MAXN];
int ten[15];

int gcd(int m, int n) {
    if (m == 0)
        return n;
    if (m > n)
        return gcd(n, m);
    else
        return gcd(m, n%m);
}

int main() {
    int t, a, b, ka, kb, n, m;
    int i, k;
    bool hascircle;

    ten[0] = 1;
    for (i=1; i<15; ++i)
        ten[i] = ten[i-1]*10;

    scanf("%d", &t);
    while (t--) {
        scanf("%s", str);
        a = b = 0;
        ka = kb = 0;
        hascircle = false;
        // ignore 0.
        for (i=2; str[i]; ++i) {
            if (str[i] == '(') {
                hascircle = true;
            } else if ( isdigit(str[i]) ) {
                if (hascircle) {
                    b = b*10+str[i]-'0';
                    kb++;
                } else {
                    a = a*10+str[i]-'0';
                    ka++;
                }
            }
        }
        // a: integer for not circle part, b: integer for circle part
        // ka: number of bits for a, kb: number of bits for b
        // result = m/n;
        if (kb) {
            n = ten[ka+kb] - ten[ka];
            m = a*ten[kb]+b-a;
        } else {
            n = ten[ka];
            m = a;
        }
        k = gcd(m, n);
        printf("%d/%d
", m/k, n/k);
#ifndef ONLINE_JUDGE
        fflush(stdout);
#endif
    }

    return 0;
}