【HDOJ】1238 Substrings

深搜+剪枝，简单字符串。

#include <stdio.h>
#include <string.h>

#define MAXLEN 105
#define MAXNUM 105

char buf[MAXNUM][MAXLEN];
char src1[MAXLEN], src2[MAXLEN];
int case_n, n;

int f(int index, int len) {
    int max = 0;
    int i=0, j, k;
    char *p;

    while (i+max < len) {
        for (j=0; j<=max; ++j)
            src1[j] = src2[max-j] = buf[index][i+j];
        src1[max+1] = src2[max+1] = '';
        k = 1;
        for (j=0; j<n; ++j) {
            p = strstr(buf[j], src1);
            if (p == NULL)
                p = strstr(buf[j], src2);
            if (p == NULL) {
                k = 0;
                break;
            }
        }
        if (k)
            ++max;
        else
            ++i;
    }

    return max;
}

int main() {
    int i, j, tmp, len;

    scanf("%d", &case_n);

    while (case_n--) {
        scanf("%d", &n);
        tmp = MAXLEN;
        for (i=0; i<n; ++i) {
            scanf("%*c%s", buf[i]);
            len = strlen(buf[i]);
            if (len < tmp) {
                tmp = len;
                j = i;
            }
        }
        tmp = f(j, tmp);
        printf("%d
", tmp);
    }

    return 0;
}