diff options
Diffstat (limited to 'I_anno')
-rw-r--r-- | I_anno/Programmazione_2/algorithms/log.cc | 25 | ||||
-rw-r--r-- | I_anno/Programmazione_2/algorithms/pow.cc | 34 | ||||
-rw-r--r-- | I_anno/Programmazione_2/algorithms/sqrt.cc | 38 |
3 files changed, 97 insertions, 0 deletions
diff --git a/I_anno/Programmazione_2/algorithms/log.cc b/I_anno/Programmazione_2/algorithms/log.cc new file mode 100644 index 0000000..1e49a2e --- /dev/null +++ b/I_anno/Programmazione_2/algorithms/log.cc @@ -0,0 +1,25 @@ +#include<iostream> + +using namespace std; + +double log(double n) { + if(n <= 2) return 1.0; + return 1.0 + log(n/2); +} + +int log2(double n) { + int a = 1; + + while(n > 2) { + n /= 2; + ++a; + } + + return a; +} + +int main() { + for(int i = 0; i < 25; ++i) + cout << i << ' ' << log(i) << ' ' << log2(i) << endl; + return 0; +} diff --git a/I_anno/Programmazione_2/algorithms/pow.cc b/I_anno/Programmazione_2/algorithms/pow.cc new file mode 100644 index 0000000..70f5b43 --- /dev/null +++ b/I_anno/Programmazione_2/algorithms/pow.cc @@ -0,0 +1,34 @@ +#include<iostream> + +using namespace std; + +int pow(int b, int e) { + if(e == 0) return 1; + int a = b; + int inc = b; + for(int i = 0; i < e-1; ++i) { + for(int j = 0; j < b-1; ++j) { + a+=inc; + } + inc = a; + } + return a; +} + +int mul(int b, int e) { + if(e == 0) return 0; + + return b+mul(b, e-1); +} + +int pow2(int b, int e) { + if(e == 0) return 1; + + return mul(b, pow(b, e-1)); +} + +int main() { + cout << pow(2, 5) << endl; + cout << pow2(2, 5) << endl; + return 0; +} diff --git a/I_anno/Programmazione_2/algorithms/sqrt.cc b/I_anno/Programmazione_2/algorithms/sqrt.cc new file mode 100644 index 0000000..01d1079 --- /dev/null +++ b/I_anno/Programmazione_2/algorithms/sqrt.cc @@ -0,0 +1,38 @@ +#include<iostream> + +using namespace std; + +double abs(double n) { + if(n < 0) return -n; + + return n; +} + + +double sq(int n) { + double x = n; + double y = 1; + while(x-y > 0.0000001) { + x = (x+y)/2; + y = n/x; + } + return x; +} + +double sq2_n(double n, double a) { + if(abs(a*a - n) <= 0.000001) { + return a; + } + + return sq2_n(n, (a+n/a)/2); +} + +double sq2(int n) { + return sq2_n(n, n/2); +} + +int main() { + cout << sq(81) << endl; + cout << sq2(81) << endl; + return 0; +} |