isdigit 返回非0表示是数字#include #include int main(){ char ch[20]; int sta=0; printf("请输入2个数字:\r\n"); while(1) {scanf("%s",&ch);
for (int l=0;l<strlen(ch);l++)
{ if (isdigit(ch[l])==0) {
printf("//it is wrong try to give two integers:\r\n");
sta=1;
break; }
}if (sta!=1){
if (l<2)
{
printf("//it is wrong try to give two integers:\r\n");
}
else
{
printf("%c%c\r\n",ch[0],ch[1]);
}}sta=0; }return 1;}
