B. Fedya and Maths
time limit per test
1 secondmemory limit per test
256 megabytesinput
standard inputoutput
standard outputFedya studies in a gymnasium. Fedya's maths hometask is to calculate the following expression:
for given value of n. Fedya managed to complete the task. Can you? Note that given number n can be extremely large (e.g. it can exceed any integer type of your programming language).
Input
The single line contains a single integer n (0 ≤ n ≤ 10105). The number doesn't contain any leading zeroes.
Output
Print the value of the expression without leading zeros.
Sample test(s)
input
4
output
4
input
124356983594583453458888889
output
0
Note
Operation x mod y means taking remainder after division x by y.
Note to the first sample:
这道题上来直接打表找规律
发现能整除4的 n 算出来是4,其他的n为0。要注意输入很大,要用字符串。
这里处理就出多说了,假设一个数字n前面n-2个数为 x 后面两个数字为 y ,则这个数 n=x*100+y
前面必然能除4,判断后面两位能否整除四即可
1 #include<cstdio> 2 #include<cmath> 3 #include<cstring> 4 #include<stdlib.h> 5 using namespace std; 6 int main() 7 { 8 char str[100005],a,b; 9 int ans; 10 scanf("%s",str); 11 int len=strlen(str); 12 if(len>=2) 13 { 14 a=str[len-1]; 15 b=str[len-2]; 16 ans=(b-'0')*10+a-'0'; 17 } 18 else 19 ans=str[len-1]-'0'; 20 21 if(ans%4==0) 22 printf("4 "); 23 else 24 printf("0 "); 25 return 0; 26 }