写一函数，求一字符长度，即编写一strlen函数

#define _CRT_SECURE_NO_WARNINGS#include<stdio.h>#include<stdlib.h>#include<math.h>#include<string.h>#include<Windows.h>int mystrlen(char *p){int i = 0;while (*p != '\0'){p++;i++;}return i;}void main(){char a[100] = "abcdefg";int count=mystrlen(a);printf("%d", count);//打印结果system("pause");}