clean/Searching.cpp at master · akumar1503/clean · GitHub

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// BINARY SEARCH
int lo = 0, hi = INF;
while(lo < hi){
    int mid = (lo + hi) / 2;
    if(f(mid) > f(mid+1)){
      lo = mid + 1;
    }
    else{
      hi = mid;
    }
}


{
// Ternary Search
double func(double x)
{
return -1*1*x*x + 2*x +3;
}


double ts(double start, double end)
{
    double l = start, r = end;

    for(int i=0; i<200; i++) {
      double l1 = (l*2+r)/3;
      double l2 = (l+2*r)/3;
      //cout<<l1<<" "<<l2<<endl;
      if(func(l1) > func(l2)) r = l2; else l = l1;
      }

     double x = l;
    return func(x);
}

}
{

// Ternary Search 2
while(lo < hi) {
    int mid = (lo + hi) >> 1;
    if(f(mid) > f(mid+1)) {
        hi = mid;
    }
    else {
        lo = mid+1;
    }
}

}