atoi函数的简单实现

#include <stdio.h>#include <ctype.h>#include <stdlib.h>#define N 100int my_atoi(char *src){int flag = 0;int num = 0;if(src[0] == '-'){flag = 1;src++;}while(*src){if(isdigit(*src)){num *= 10;num += *src - '0';src++;}elsebreak;}if(flag)num = -num;return num;}int main(void){char *str = "1234.567";printf("%d\n",my_atoi(str));printf("%d\n",atoi(str));return 0;}