Niven Numbers
Source : Unknown | |||
Time limit : 1 sec | Memory limit : 32 M |
Submitted : 5349, Accepted : 965
A Niven number is a number such that the sum of its digits divides itself. For example, 111 is a Niven number because the sum of its digits is 3, which divides 111. We can also specify a number in another base b, and a number in base b is a Niven number if the sum of its digits divides its value.
Given b (2 <= b <= 10) and a number in base b, determine whether it is a Niven number or not.
Input
Each line of input contains the base b, followed by a string of digits representing a positive integer in that base. There are no leading zeroes. The input is terminated by a line consisting of 0 alone.
Output
For each case, print "yes" on a line if the given number is a Niven number, and "no" otherwise.
Sample Input
10 111 2 110 10 123 6 1000 8 2314 0
Sample Output
yes yes no yes no
本题意思为给定一个进制(base),然后给一个在base进制下的数字NUM,判断NUM是否为尼玛数(NUM能否被NUM各位数字之和整除)
由于NUM的大小限制在int内,而base会让int型超出范围,比如8(10) = 1000(2),所以NUM需要为字符串类。第二个关键在于溢出处理,同HOJ1008中,
整除判断可以变求余边扩展。
1 #include<iostream> 2 using namespace std; 3 #include<string> 4 5 int main(){ 6 int base; string num; 7 while(cin>>base && base != 0){ 8 cin>>num; 9 int x = 0; int y = 0; 10 for(int i = 0;i < num.length();i++){ 11 x += num[i] - '0'; 12 } 13 for(int i = 0;i < num.length();i++){ 14 y = y * base + num[i] - '0'; 15 y %= x; 16 } 17 18 if(y == 0){ 19 printf("yes "); 20 }else{ 21 printf("no "); 22 } 23 } 24 return 0; 25 }