A Simple Math Problem
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 2505 Accepted Submission(s): 777
Problem Description
Given two positive integers a and b,find suitable X and Y to meet the conditions: X+Y=a Least Common Multiple (X, Y) =b
Input
Input includes multiple sets of test data.Each test data occupies one line,including two positive integers a(1≤a≤2*10^4),b(1≤b≤10^9),and their meanings are shown in the description.Contains most of the 12W test cases.
Output
For each set of input data,output a line of two integers,representing X, Y.If you cannot find such X and Y,output one line of "No Solution"(without quotation).
Sample Input
6 8 798 10780
Sample Output
No Solution 308 490
一道纯的数学题。
题意:给出两个数 a,b。a是x和y的和,b是x和y的最小公倍数;
在这里根据两个数互质,则他们的和与他们的积也互质可以推导出a和b的最大公因数就是x和y的最大公因数。
然后解方程,在这里注意一下,求得的解必须是整数。
#include<stdio.h>
#include<math.h>
#define ll long long
using namespace std;
ll gcd(ll a,ll b)
{ while(b!=0)
{ll c=a%b;
a=b;
b=c;
}
return a;
}
ll lcm(ll a,ll b)
{
return a/gcd(a,b)*b;
}
int main()
{
ll a,b;
while(scanf("%lld%lld",&a,&b)!=EOF)
{
ll c=gcd(a,b);
c=b*c;
ll d=a-sqrt(a*a-4*c);
ll p=d/2;
if(a*a-4*c<0)
printf("No Solution\n");
else
{
ll z=a*a-4*c;
ll s=sqrt(z);
if(s*s==z&&p*2==d)
printf("%lld %lld\n",p,a-p);
else
printf("No Solution\n");
}
}
}