#include<iostream.h>
0 }3 l' r7 I3 }" _2 q#include<math.h>$ ]+ A8 v" t' o' A
double fx(int n,double p[],double x)8 K& v) ]$ o- R5 W
{: {7 f& Q. ~4 T9 D& z
double z=0,y=1;
0 R8 @' I+ I7 i5 y* }7 D int i=0,j=0;* {, c5 f& d6 `7 v
for(;i<n+1;i++). _. x- t( Q. t6 R1 k4 s
{ $ \$ J7 V3 \. [( Z0 V0 v* x( X, f: b
for(;j<i;j++)
; _, c1 L6 l$ o$ Z! F9 w y*=x;
3 M& R( z# I z5 m. v, }; E z+=*(p+i)*y;7 H1 W0 B& R& b
}
: s* ~# v ^8 X/ f& K5 ~* | return z;" q w0 g! w+ D' j
}
* o6 i# i3 p3 i- o. vint fi(int k)
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if(k==0)
, o% Z* w# T) E1 M return 1;/ ^) K4 E8 _0 _; j; Y$ p& a: j
else 1 S" [: I( w d
{, x3 K! s: } P6 f. S# J2 I O
if(k==1)) Y5 f+ b1 X! w4 X
return 1;
5 o6 p! N8 C( S' K# ~% Y9 e else - d5 Y- V! M! w d2 u/ @
{$ E5 G6 a" |5 T6 U0 t) Z! s
int i=0,i1=1,i2=1,w=0;
1 N5 P# n) x. L* ]5 e0 J for(;i<k-1;i++)
) W; u9 s/ Q4 o4 @) X {( {0 u/ F0 l9 o' ~
w=i1+i2;5 i% y' W4 L% R r/ _
i1=i2;6 F3 ?7 s; U5 l
i2=w;
: {$ w/ ]4 K, ?( T1 q8 Z/ Y7 w' x& M% y }
6 \" a/ X+ ]3 y% b. k return w;
# g3 l0 H; @7 V h }
6 {% z+ j$ d) H# e+ e7 Q4 `}9 J: { Z0 W$ d! c v" t+ H1 u
}
# s. F6 |1 V& k. ^. ^( O) \3 fint r(double w,double a,double b); l! n/ ]+ \" [ @
{8 z8 O8 b! |1 m3 w' r
int i=0;
( d4 e, H1 O e' L for(;fi(i)<=(b-a)/w;i++)2 p+ ~4 R0 g& j9 {" l
{}9 |* n" b5 n( n. t \# Y$ ~
return i;7 ?: R/ h* [4 B) [' O, i) @
}
: ~" c' @. D7 S7 }7 O, _0 @void main()
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cout<<"输入函数的最高次幂";, p- e3 S' J/ \- k( s4 g
int n; V6 {( h+ ]; I1 z& f' v
cin>>n;4 B, o% K5 Y, K: C
double *p=new double[n+1];8 i4 S; h; l6 y% j* U1 N( V/ J
double a,b,g=0,j=0,c=0;
( g' y3 h$ k$ Q" h& b& s. |- X cout<<"依升降幂输入x项的系数"<<endl;
T) b4 D- {& }' F$ b# E* \ for(int i=0;i<n+1;i++)9 {. G# e1 O& Y* Z4 ]! k
cin>>*(p+i);
" ?# T. j7 K# A) W# i cout<<"输入误差值"<<endl;
! C; d5 i5 t. g$ K* A1 O double w;
P$ d* o$ a& }: B6 N2 g; A) o6 O7 | cin>>w;" p+ v( z2 y3 V0 O' n. A# Z
cout<<"输入初始区间"<<endl;
Y: K' `& `( Y4 S9 m2 ? cin>>a>>b;3 A& F4 @* R5 }* W+ R
cout<<"输入辨别常数"<<endl;$ N4 [) x8 B7 k! K# t, L/ |
cin>>c;
! `3 ^! x6 Y' a. r0 x9 P n=r(w,a,b);5 _: p$ q) y! Y; n9 r, G5 d R
i=0;
2 N! s& [/ h l& A& E6 f cout<<fi(n-i-2)<<endl;" [! F0 I* O: S4 M) u B: K0 T
cout<<a<<" "<<b;
7 Y2 n1 e1 E$ _$ Q$ k/ v g=a+fi(n-2-i)*(b-a)/fi(n-i);
$ ]8 U/ P- H3 f, Z" m& w j=a+fi(n-1-i)*(b-a)/fi(n-i);; m2 V% p) e. u/ q8 w
cout<<g<<" "<<j;1 q/ z+ b( y5 {8 v ~
for(i=1;i<n-1;i++)
* u! @8 P4 P6 v6 }/ J {
9 t0 f) Q# S4 p8 v/ l
9 W5 u/ Z. f7 w% ^ F9 B8 _ 8 n2 s s" @& M2 {' k' b
if(fx(n,p,g)>fx(n,p,j))
- F, k$ G1 V: B9 K6 r {
- H* @3 H: ^- n+ y% N a=g;
( Y. ~$ \' ^& l4 z. Y g=j;
( }9 P4 s5 V# ~/ ]; N- k j=a+fi(n-1-i)*(b-a)/fi(n-i);/ g$ _$ G1 C; e% w" q
}
- }( ~( S# _/ E( S6 B m9 o else
" p3 s s1 J/ ^* W3 i9 b0 e9 P {, J' U3 D: c1 \4 D, r& a; m
b=j;: f3 p# q" f9 Q8 g* L# F
j=g;4 R# f/ y% }' ^* D4 R
g=a+fi(n-2-i)*(b-a)/fi(n-i);, J) S* a8 D f/ a- C: b
}
& B4 A7 R( n$ t/ ?5 {4 } 4 G, [4 p( R3 O. H+ [( U3 n
}
- C9 H! M P& p. \+ ` j=g+c;4 T$ x) P4 c, g; x, T: c
if(fx(n,p,g)>fx(n,p,j))
. B4 c1 w1 r: X2 T6 n a=g;
+ _* U1 W1 y6 u/ [ else b=g;
5 ?- o5 q$ k' }" {5 W5 R cout<<"函数值在 ("<<g<<","<<j<<")之间;";
- I3 D8 ?; g! u( f \; G$ a& Y; W) b
}. l8 t( D0 u% \! v
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