从字符串中找出连续最长数字串

char* continueMax(char *intput)
{
if(!input)
return 0;
char *head=input ;
char *output=nullptr;
int  Max=0;
while(*head){
if(*head>'9'&&*head<'0'){
++head ;
++input;
}else if(*input>'9'||*input<'0'||input=='\0'){
if(Max<input-head){
Max=input-head;
output=head;
}
head=input;
}else{
++input;
}
}
*(output+Max)='\0';
return output;
}