57 lines
1.5 KiB
C++
57 lines
1.5 KiB
C++
#include<iostream>
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#include<cstdio>
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#include<cstring>
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#include<cmath>
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using namespace std;
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double a,b,c,d,L,R;
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double f(double x)
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{
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return fabs(a*x*x*x+b*x*x+c*x+d);
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}
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const double eps=1e-9;
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int dcmp(double x)
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{
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if(fabs(x)<=eps)return 0;
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else return x<0?-1:1;
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}
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bool judge(double x)
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{
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return x<=R&&x>=L;
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}
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int main()
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{
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while(scanf("%lf%lf%lf%lf%lf%lf",&a,&b,&c,&d,&L,&R)!=EOF)
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{
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double delta=4*b*b-12*a*c;
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double ans;
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if(dcmp(a)==0)
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{
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double mid=-c/2/b;
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if(judge(mid))
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ans=max(f(mid),f(L));
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else ans=f(L);
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ans=max(ans,f(R));
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}
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else if(delta<=0)
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{
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ans=max(f(L),f(R));
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}
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else
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{
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delta=sqrt(delta);
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double x1=-2*b+delta;
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x1=x1/6/a;
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double x2=-2*b-delta;
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x2=x2/6/a;
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ans=f(L);
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ans=max(ans,f(R));
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if(judge(x1))
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ans=max(ans,f(x1));
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if(judge(x2))
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ans=max(ans,f(x2));
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}
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printf("%.2lf\n",ans);
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}
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return 0;
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}
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