标签:algorithm
#include <cstdio>
#include <iostream>
#include <string>
using namespace std;
#ifdef ONLINE_JUDGE
#define FINPUT(file) 0
#define FOUTPUT(file) 0
#else
#define FINPUT(file) freopen(file,"r",stdin)
#define FOUTPUT(file) freopen(file,"w",stdout)
#endif
unsigned int sumOfDigits(string s)
{
unsigned int sum = 0;
int i = 0;
while(i<s.length())
{
sum += s[i]-‘0‘;
i++;
}
return sum;
}
unsigned int sumOfDigits2(unsigned int n)
{
unsigned int sum = 0;
while(n!=0)
{
sum += n%10;
n/=10;
}
return sum;
}
int main()
{
FINPUT("in.txt");
FOUTPUT("out.txt");
string s;
while(cin>>s && s!="0")
{
int sum = sumOfDigits(s);
while(sum>=10)
{
sum = sumOfDigits2(sum);
}
cout<<sum<<endl;
}
return 0;
}标签:algorithm
原文地址:http://blog.csdn.net/daringpig/article/details/25461611