atoi函数实现_buwanmei

//字符串转换成整数atoi函数的实现#include <iostream>#include <assert.h>using namespace std;int atoi_mf(char s[]){assert(s != NULL);int i = 0;int sum = 0;int sign;//跳过空格和制表符while(' ' == s[i] || '\t' == s[i]){i++;}//检测整数的符号sign = ('-'==s[i] ? -1:1);//跳过符号if('-' == s[i] || '+' == s[i]){i++;}//while(s[i] != '\0'){if(s[i] >= '0' && s[i] <= '9'){sum = s[i]-'0'+sum*10;}else{break;}i++;}return sign*sum;}void main(){char *str = "-12dd34";cout << atoi_mf(str) <<endl;}