直接看代码：

//求字符串中子字符串出现的次数
//例如：char *p = "abcd1111222abcd333444abcd555666aa"
//求字符串p中"abcd"出现的次数
#include <stdlib.h>
#include <stdio.h>
#include <string.h>   //这三个是常规的头文件int getSubCount(char *p/*in*/,char *sub/*in*/,int *ncount)
{                       //这里是函数实现，与主函数分开if(NULL == p || NULL == sub || NULL == ncount){                 //这里是数据有效性验证return -1;}char *q = p;int temCount = 0;do{q = strstr(q,sub);  //返回sub首次出现在q中的位置。if(q != NULL){temCount++;q = q +strlen(sub);}else{break;}}while( *q != '\0');*ncount = temCount;	return 0;
}int main()
{char *p = (char *)"abcd11abcd2abcd333444abcd555666aa";  //vs默认生成的是const char *，强制转换一下char* sub = (char*)"abcd";int ncount = 0;int ret = 0;ret = getSubCount(p,sub,&ncount);if(ret!=0){printf("func getSubCount(char *p/*in*/,char *sub/*in*/,int *ncount) err : %d\n",ret);return -1;    //输出异常}printf("ncount = %d\n",ncount);return 0;	
}