Create 1666.cpp

QUSTOJ/1666.cpp

@@ -0,0 +1,44 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <cmath>
+ 
+ 
+ 
+double a,b,c,d,L,R;
+double delta;
+double x1,x2;
+ 
+double fx1,fx2,fL,fR;
+ 
+int ans=0;
+int i;
+double maxvalue=0;
+ 
+double* data[4]={&fL,&fR,&fx1,&fx2};
+ 
+int main()
+{
+    while(scanf("%lf %lf %lf %lf %lf %lf",&a,&b,&c,&d,&L,&R)==6)
+    {
+        ans=2;
+        delta=b*b-3*a*c;
+        fL=fabs(a*L*L*L+b*L*L+c*L+d);
+        fR=fabs(a*R*R*R+b*R*R+c*R+d);
+        if(delta>0)
+        {
+            x1=(-b-sqrt(delta))/(3*a);
+            x2=(sqrt(delta)-b)/(3*a);
+            fx1=fabs(a*x1*x1*x1+b*x1*x1+c*x1+d);
+            fx2=fabs(a*x2*x2*x2+b*x2*x2+c*x2+d);
+            ans=4;
+        }
+        maxvalue=*data[0];
+        for(i=1;i<ans;i++)
+        {
+            if(*data[i]>maxvalue) maxvalue=*data[i];
+        }
+        printf("%.5lf\n",maxvalue);
+    }
+    return 0;
+}