主要特征
1、没有预处理阶段
2、需要常量额外空间
3、通常需要模式串窗口向右移动一个位置
4、可以按照任意顺序进行比较
5、搜索的时间复杂度为O(mn)
6、文本字符期望比较次数:2n
本文地址：http://www.cnblogs.com/archimedes/p/brute-force-algorithm.html，转载请注明源地址。
算法描述
暴力搜索算法由文本串中从0到n-m所有位置的比较组成，无论是否从模式串的起始位置开始，每次匹配过后，模式串向右移动一位。暴力搜索算法没有预处理阶段，文本串和模式串需要常量额外空间，在搜索阶段的文本串的字符可以按照任意顺序进行比较，匹配的时间复杂度为O(mn)，
C代码实现
int BF(char *x, int m, char *y, int n) {
int i, j;
/* 搜索*/
for (j = 0; j <= n - m; ++j) {
for (i = 0; i < m && x[i] == y[i + j]; ++i);
if (i >= m)
return j;
}
}
上面的算法可以改写为下面更加高效的算法：
#define EOS ' '
int BF(char *x, int m, char *y, int n) {
char *yb;
/* 匹配*/
for (yb = y; *y != EOS; ++y)
if (memcmp(x, y, m) == 0)
return y - yb;
}
举例
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第8次尝试
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第9次尝试
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第13次尝试
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第15次尝试
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第17次尝试
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