diff options
author | Santo Cariotti <dcariotti24@gmail.com> | 2020-07-19 22:58:15 +0200 |
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committer | Santo Cariotti <dcariotti24@gmail.com> | 2020-07-19 22:58:15 +0200 |
commit | 7468f361189f9a32fb7d02e033d7174a3c1ef182 (patch) | |
tree | c0e3d35997b4dee3a30baca321df4289b90cbac2 /I_anno/Programmazione_2/algorithms | |
parent | 3833c952f1dff3957bc423045df6d52c14a6db78 (diff) |
chore: binary search
Diffstat (limited to 'I_anno/Programmazione_2/algorithms')
-rw-r--r-- | I_anno/Programmazione_2/algorithms/binarysearch.cc | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/I_anno/Programmazione_2/algorithms/binarysearch.cc b/I_anno/Programmazione_2/algorithms/binarysearch.cc new file mode 100644 index 0000000..c9b4cd7 --- /dev/null +++ b/I_anno/Programmazione_2/algorithms/binarysearch.cc @@ -0,0 +1,33 @@ +#include<iostream> + +using namespace std; + +bool bs(int a[], int i, int j, int x) { + if(j<i) return false; + int mid = i+(j-i)/2; + if(a[mid] == x) + return true; + if(a[mid] > x) + return bs(a, i, mid-1, x); + return bs(a, mid+1, j, x); +} + +bool bs2(int a[], int i, int j, int x) { + while(i <= j) { + int mid = i+(j-i)/2; + if(a[mid] == x) return true; + if(a[mid] < x) + i = mid+1; + else + j = mid-1; + } + return false; +} + +int main() { + int a[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; + for(int i = 0; i < 12; ++i) + cout << i << ' '<<bs(a, 0, 9, i) << ' ' << bs2(a, 0, 9, i) << endl; + return 0; +} + |