1.atoi函数实现
int atoint(const char * string)
{
int n = 0;
int i;
for(i = 0; string[i] >= '0' && string[i] <= '9'; i++)
{ n = 10*n + string[i] - '0';
continue;}
return n;
}
int main()
{
char *p;
char buffer[20];
int sum;
p=buffer;
printf("please input string:/n");
scanf("%s",buffer);
sum=atoint(p);
printf("%d",sum);
return 0;
}
2.itoa函数实现
void itochar(int num)
{
int i = 0;
int j ;
char stra[10];
char strb[10];
while ( num )
{
stra[i++]=num%10+48;
num=num/10;
}
stra[i] = '/0';
for( j=0; j < i; j++)
{
strb[j] = stra[i-j-1];
}
strb[j] = '/0';
printf(strb);
}
int main()
{
int num;
scanf("%d",&num);
itochar(num);
return 0;
}
/