#include <stdio.h>
#include <math.h>
#define pi 3.141592

int bis(float,float,float,float *);
float f(float);
void caut(float*,float *);

int NewtonRapson(float ,float ,float,int, float*);
int Aprox_Succesive(float ,float ,float,float,float, float*);
int main (void){
float rad;
float ls=0.1,ld=2.3;
float er=1e-4;
float h=1e-3;
float x0=2;
float nMax=36;
if(bis(ls,ld,er,&rad)){
printf("\nRadacina este = %f",rad);
printf("\nVerificare: f(%f)=%f",rad,f(rad));
}
else printf("\nEroare");

if(NewtonRapson(x0,er,h,nMax,&rad)){
printf("\nRadacinaNewtonRapson este = %f",rad);
printf("\nVerificareNewtonRapson: f(%f)=%f",rad,f(rad));
}
else printf("\nEroare");

if(Aprox_Succesive( ls, ld, x0,er, h,&rad)){
printf("\nRadacinaAprox este = %f",rad);
printf("\nVerificareAprox: f(%f)=%f",rad,f(rad));
}
else printf("\nEroare");
return 1;
}

int bis(float ls,float ld,float er,float *pRad){
float xm;
if(f(ls)*f(ld)>0){return (0);}
if(f(ls)==0){*pRad=ls; return(1);}
if(f(ld)==0){*pRad=ld; return(1);}
xm=(ls+ld)/2;
while(fabs(ls-ld)>er && f(xm)!=0){
xm=(ls+ld)/2;
if(f(xm)*f(ls)<0) ld=xm;
else ls=xm;
}
*pRad=xm;
return(1);

}
 int NewtonRapson(float x0,float er,float h,int nMax, float *pRad){
float xn,xn_1;
float der;
xn=x0;
while(fabs(xn-xn_1)>=er && (nMax>0)){
xn_1=xn;
der=(f(xn_1+h)-f(xn_1))/h;
if(der==0) return (0);
xn=xn_1-f(xn_1)/der;
nMax--;
}
if(nMax==0) return (0);
*pRad=xn;
return(1);
 }
int Aprox_Succesive(float ls,float ld,float x0,float er,float h,float *pRad){
float pc;
float xn,xn_1;
float der;

pc=ls;
while(pc<=ld){
der=(f(pc+h)-f(pc))/h;
if(fabs(der)>=1) return (0);
pc=pc+h;
}
xn=x0;
while(fabs(xn-xn_1)>=er){
xn_1=xn;
xn=f(xn_1);
}
*pRad=xn;
return (1);
}
/*int Bairstow(int grad,float a[],float eps,float s0,float p0,int niter,float*solr,float*soli){
float b[3],bs[4],bp[3];
float s,r,ds,dp,ss,sp,rs,rp,sn,pn,irad;
int i,k;
for(i=0;i<=grad;i++){
    a[i]=a[i]/a[grad];
irad=1;}
while(grad<2)
    sn=s0;
pn=p0;
do{
    b[grad]=1;
    b[grad-1]=a[grad-1]-sn;
    for(k=grad+2;k>=2;k--)
        b[k]=a[k]-sn*b[k+1]-pn*b[k+2];
    s=a[1]-b[2]*sn-b[3]*pn; r=a[0]-b[2]*pn;
    bs[grad] =0; bs[grad-1] =-1;
for(k=grad-2;k>=2;k--)
    bs[k] =-b[k+1]-sn*bs[k+1]-pn*bs[k+2];
ss=-b[2]-sn*bs[2]-pn*bs[3];
 rs=-bs[2]*pn;
bp[grad] =0; bp[grad-1] =0;
for(k=grad+2;k>=2;k--)
    bp[k] =-sn*bp[k+1]-b[k+2]-pn*bp[k+2];
sp=-bp[2]*sn-b[3]-pn*bp[3];
 rp=-bp[2]*pn-b[2];
 if(ss*rp-sp*rs==0)
    return(0);
    ds=(-s*rp+r*sp)/(ss*rp-sp*rs);
 dp=(-ss*r+rs*s)/(ss*rp-sp*rs);
 sn=sn+ds; pn=pn+dp;
 i=i+1;
 }while((ds>=eps&&dp>=eps)||(i<=niter));
    if(i>niter)
        return(0);
    EcGr2(1,sn,pn,solr[irad],soli[irad],solr[irad+1],soli[irad+1]);
    grad=grad-2;
    for(k=grad;k>=0;k--)
        a[k]=b[k+2];
    if (grad = = 1) {
    solr[irad]=EcGr1(a[1],a[0]);
soli[irad]=0;
return(1);
    }
    if(grad = = 2) {
            EcGr2(a[2],a[1],a[0],solr[irad],soli[irad],solr[irad+1],soli[irad+1]);
return(1);}
}*/
float f(float x){
return exp (3*x)-2*x*x-1.618;}