题目：hdu4847:Wow! Such Doge!

题目大意：在给出的段落里面找出“doge”出现的次数。大写和小写都能够。

解题思路：字符串匹配问题，能够在之前将字母都转换成统一格式。

代码：

#include <stdio.h>

#include <string.h>

const int N = 1e6;

char str[N];

const char *s1 = "doge";

int find () {

	int sum = 0;

	char *p = strstr(str, s1);

	while (p != NULL) {

		sum++;

		p = p + 4;

		//if (*p == '\0')

		//	break;

		p = strstr (p, s1);

	}

	return sum;

}

int main () {

	int count = 0;

	while (scanf ("%s", str) != EOF) {

		for (int i = 0; i < strlen (str); i++)

			if (str[i] >= 'A' && str[i] <= 'Z')

				str[i] += 32;

		count += find ();

	}

	printf ("%d\n", count);

	return 0;

}