C语言，查找子字符串并统计个数

一、C语言，在一个字符串中查找一个子字符串，并统计个数~

EX：

#include <stdio.h>
#include <string.h>
int find_string(char str[],char substr[]);
int main()
{
    /*
    char ch[10] = {"qweasd"};
    int n = strlen(ch);
    int sn = sizeof(ch);
    printf("%d
", n);
    printf("%d
",sn);
    */
    char ch1[] = "12";
    char ch2[] = "323 12j34312j 434212435 412";
    int sum = find_string(ch2,ch1);
    printf("%d
",sum);

    return 0;
}

int find_string(char str[], char substr[])
{
    int count = 0,i,j,check;
    int len = strlen(str);
    int sublen = strlen(substr);
    for(i = 0; i < len; i++)
    {
        check = 1;
        for(j = 0; j + i < len && j < sublen; j++)
        {
            if(str[i+j] != substr[j])
            {
                check = 0;
                break;
            }
        }
        if(check == 1)
        {
            count++;
            i = i + sublen;
        }
    }

    return count;
}

二、从二维数组中查找指定长度的回文字符串

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

int main()
{
    char ch[8][8] = {{'z','x','x','e','z','c','x','z'},{'q','w','p','q','e','w','r','e'},{'q','w','e','e','w','a','q','w'},{'q','e','w','q','e','r','r','e'},
                        {'q','w','e','e','w','q','e','r'},{'q','w','w','q','e','r','r','e'},{'q','w','e','e','w','q','e','r'},{'q','w','w','q','e','r','r','e'}};
    int i,j,k,len,check = 0,count = 0;
    int length = 4; //查找长度
    for(i=0; i<8; i++)
    {
        for(j=0; j <= 8-length; j++)
        {
            /*
            check = 0;
            for(k=0; k<length/2; k++)
            {
                if(ch[i][j+k] != ch[i][j+length-k-1])
                {
                    check = 1;
                    break;
                }
            }
            if(check == 0)
            {
                count++;
            }*/
            
            len = 0;
            while((ch[i][j+len] == ch[i][j+length-len-1]) && j+len < 8)
            {
                if(len == length/2)
                {
                    count++;
                    break;
                }
                len++;
            }
        }
    }
    printf("count:%d
",count);

    return 0;
}