Problem Description
Jam has a math problem. He just learned factorization. He is trying to factorize ax^2+bx+cax?2??+bx+c into the form of pqx^2+(qk+mp)x+km=(px+k)(qx+m)pqx?2??+(qk+mp)x+km=(px+k)(qx+m). He could only solve the problem in which p,q,m,k are positive numbers. Please help him determine whether the expression could be factorized with p,q,m,k being postive.
Input
The first line is a number TT, means there are T(1 \leq T \leq 100 )T(1≤T≤100) cases
Each case has one line,the line has 33 numbers a,b,c (1 \leq a,b,c \leq 100000000)a,b,c(1≤a,b,c≤100000000)
Output
You should output the "YES" or "NO".
Sample Input
2 1 6 5 1 6 4
Sample Output
Copy
YES NO
Hint
The first case turn x^2+6*x+5x?2??+6∗x+5 into (x+1)(x+5)(x+1)(x+5)
题意:给你一个一元二次方程的三个系数a ,b,c问你是否能用十字相乘的方法分解这个式子
题解:直接暴力枚举,当然要优化下枚举的方法,不然会超时滴,优化:因为最大数据是一亿,一亿可以分解为一万乘一万,因为这样我们分解的两个数一定不可能超过一万,先将c的所有因子存在数组中,然后在计算出a的所有因子,一个一个试即可
#include<stdio.h> #include<string.h> #include<string> #include<math.h> #include<algorithm> #define LL long long #define PI atan(1.0)*4 #define DD doublea #define MAX 10100 #define mod 10007 using namespace std; int ans[MAX]; int main() { int n,m,j,i,t,k; int a,b,c,Min1,Min2; scanf("%d",&t); while(t--) { scanf("%d%d%d",&a,&b,&c); Min1=min(a,10000); Min2=min(c,10000); k=1;n=m=1; for(i=1;i<=Min2;i++) { n=c/i; if(n*i==c) ans[k++]=i; } int flag=0; for(i=1;i<=Min1;i++) { m=a/i; if(i*m==a) { for(j=1;j<k;j++) { if((i*ans[j]+m*(c/ans[j])==b)||(m*ans[j]+i*(c/ans[j])==b)) { flag=1; break; } } } if(flag) break; } if(flag) printf("YES\n"); else printf("NO\n"); } return 0; }
BestCoder Round #70 Jam's math problem(hdu 5615)