题解 | #Digital Roots#
Digital Roots
https://www.nowcoder.com/practice/cef727d0af33479c9fb4a9c120702414
#include <stdio.h>
int main() {
int num,sum;
while(scanf("%d",&num)!=EOF){
if(num<10)
printf("%d\n",num);
else{
do{
sum=0;
while(num>0){
sum=sum+num%10;
num=num/10;
}
num=sum;
}while(sum>=10);
}
printf("%d\n",sum);
}
return 0;
}
