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Linear Search 線性搜尋: char names[100][10];
char target[20]="EGG"; 1 2 3 4 5 6 7 8 99 CAT GOA ADA FISH DOG BOY HEN EGG KEN … for (i=0;i<100;i++) if (strcmp(names[i],target)==0) break; if ( ) printf ("found!\n"); else printf ("not found!\n"); i<100 2019年7月27日 Sorting & Searching
![ Linear Search 線性搜尋: char names[100][10];](http://slideplayer.com/slide/17176980/99/images/1/%EF%83%BD+%EF%83%BD+%EF%83%BD+%EF%83%BD+%EF%83%BD+%EF%83%BD+%EF%83%BD+%EF%83%BE+Linear+Search+%E7%B7%9A%E6%80%A7%E6%90%9C%E5%B0%8B%3A+char+names%5B100%5D%5B10%5D%3B.jpg "char target[20]= EGG ; CAT. GOA. ADA. FISH. DOG. BOY. HEN. EGG. KEN. … for (i=0;i<100;i++) if (strcmp(names[i],target)==0) break; if ( ) printf ( found!\n ); else. printf ( not found!\n ); i< 年7月27日. Sorting & Searching.")
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1 char A[10][5]; char target[5]="HEN"; int lo=0, hi=9, mid;
Binary Search 二分搜尋: 1 lo=mid+1 mid=(lo+hi)/2 mid mid lo lo hi 1 2 3 4 5 6 7 8 9 ADA BOY CAT DOG EGG FISH GOA HEN IDA KEN A[i] No Yes A[mid]=target ?? A[mid]=target ?? 2019年7月27日 Sorting & Searching
![1 char A[10][5]; char target[5]= HEN ; int lo=0, hi=9, mid;](http://slideplayer.com/slide/17176980/99/images/2/1+char+A%5B10%5D%5B5%5D%3B+char+target%5B5%5D%3D+HEN+%3B+int+lo%3D0%2C+hi%3D9%2C+mid%3B.jpg "Binary Search 二分搜尋: 1. lo=mid+1. mid=(lo+hi)/2. mid. mid. lo. lo. hi ADA. BOY. CAT. DOG. EGG. FISH. GOA. HEN. IDA. KEN. A[i] No. Yes. A[mid]=target A[mid]=target 2019年7月27日. Sorting & Searching.")
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2 char A[10][5]; char target[5]="CAT"; int lo=0, hi=9, mid;
Binary Search 二分搜尋: 2 mid=(lo+hi)/2 lo=mid+1 hi=mid-1 lo mid mid lo hi 1 2 3 4 5 6 7 8 9 ADA BOY CAT DOG EGG FISH GOA HEN IDA KEN hi A[i] No Yes No A[mid]=target ?? A[mid]=target ?? 2019年7月27日 Sorting & Searching
![2 char A[10][5]; char target[5]= CAT ; int lo=0, hi=9, mid;](http://slideplayer.com/slide/17176980/99/images/3/2+char+A%5B10%5D%5B5%5D%3B+char+target%5B5%5D%3D+CAT+%3B+int+lo%3D0%2C+hi%3D9%2C+mid%3B.jpg "Binary Search 二分搜尋: 2. mid=(lo+hi)/2. lo=mid+1. hi=mid-1. lo. mid. mid. lo. hi ADA. BOY. CAT. DOG. EGG. FISH. GOA. HEN. IDA. KEN. hi. A[i] No. Yes. No. A[mid]=target A[mid]=target 2019年7月27日. Sorting & Searching.")
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3 char A[10][5]; char target[5]="CAT"; int lo=0, hi=9, mid;
Binary Search 二分搜尋: "CAB" 3 mid=(lo+hi)/2 lo lo=mid+1 hi=mid-1 mid mid lo hi 1 2 3 4 5 6 7 8 9 ADA BOY CAT DOG EGG FISH GOA HEN IDA KEN hi A[i] No No No target < A[mid] hi<lo not found 2019年7月27日 Sorting & Searching
![3 char A[10][5]; char target[5]= CAT ; int lo=0, hi=9, mid;](http://slideplayer.com/slide/17176980/99/images/4/3+char+A%5B10%5D%5B5%5D%3B+char+target%5B5%5D%3D+CAT+%3B+int+lo%3D0%2C+hi%3D9%2C+mid%3B.jpg "Binary Search 二分搜尋: CAB 3. mid=(lo+hi)/2. lo. lo=mid+1. hi=mid-1. mid. mid. lo. hi ADA. BOY. CAT. DOG. EGG. FISH. GOA. HEN. IDA. KEN. hi. A[i] No. No. No. target < A[mid] hi<lo not found. 2019年7月27日. Sorting & Searching.")
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4 二分搜尋 Binary Search int binarySearch (char target[]){
int lo=0, hi=9, mid, pos, n; pos = -1; // not found return pos; } 4 while ( ){ } lo<=hi && pos<0 mid = (lo+hi)/2; n = strcmp (target, A[mid]); pos = mid; if (n==0) else if (n<0) else hi = mid-1; lo = mid+1; mid lo hi 1 2 3 4 5 6 7 8 9 ADA BOY CAT DOG EGG FISH GOA HEN IDA KEN 2019年7月27日 Sorting & Searching A[i]
![4 二分搜尋 Binary Search int binarySearch (char target[]){](http://slideplayer.com/slide/17176980/99/images/5/4+%E4%BA%8C%E5%88%86%E6%90%9C%E5%B0%8B+Binary+Search+int+binarySearch+%28char+target%5B%5D%29%7B.jpg "int lo=0, hi=9, mid, pos, n; pos = -1; // not found. return pos; } 4. while ( ){ } lo<=hi && pos<0. mid = (lo+hi)/2; n = strcmp (target, A[mid]); pos = mid; if (n==0) else if (n<0) else. hi = mid-1; lo = mid+1; mid. lo. hi ADA. BOY. CAT. DOG. EGG. FISH. GOA. HEN. IDA. KEN. 2019年7月27日. Sorting & Searching. A[i]")
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