Đây là một chương trình C ++ để tìm kiếm nhiều lần trên cùng một văn bản.
Thuật toán
Begin Take the original string and pattern to be searched as input. org_len = store the length of original string pat_len = store the length of pattern for i = 0 to (org_len - pat_len) for j = 0 to pat_len - 1 if (org[i + j] != patt[j]) if (j == pat_len) Increase m. Print the position at which the pattern is found if (m == 0) Print no match found else Print the total number of instances found. return 0 End
Ví dụ
#include<iostream>
#include<string.h>
using namespace std;
int main() {
char org[150], patt[150];
int i, j, m = 0, org_len, pat_len;
cout << "\nEnter Original String:";
cin >> org;
cout << "Enter Pattern to Search:";
cin >> patt;
org_len = strlen(org); //store the length of original string
pat_len = strlen(patt); //store the length of pattern
for (i = 0; i <= (org_len - pat_len); i++) {
for (j = 0; j < pat_len; j++) {
if (org[i + j] != patt[j])
break;
}
if (j == pat_len) {
m++;
cout << "\nPattern Found at Position: " << i;
}
} if (m == 0)
cout << "\nNo Match Found.";
else
cout << "\nTotal Number of Instances Found = " << m;
return 0;
} Đầu ra
Enter Original String:thisistutorialspoint.thisisac++program Enter Pattern to Search:is Pattern Found at Position: 2 Pattern Found at Position: 4 Pattern Found at Position: 23 Pattern Found at Position: 25 Total Number of Instances Found = 4