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@ItsBenyaamin
Created April 23, 2023 15:45
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a program to find a start index of a word in a phrase
#include <iostream>
#include <string>
using namespace std;
string getStringFromInput(int length);
int searchForTheQuery(string totalPhrase, string queryPhrase);
int main()
{
int n, m;
cout << "Please enter total length of string: ";
cin >> n;
cout << "Please enter length of query: ";
cin >> m;
string totalPhrase = getStringFromInput(n);
string queryPhrase = getStringFromInput(m);
int index = searchForTheQuery(totalPhrase, queryPhrase);
if(index != -1) {
cout << "Start index of query: " << index;
}else {
cout << "Index not found!";
}
return 0;
}
string getStringFromInput(int length) {
string inputedString;
while(true) {
cout << "Please enter an string with length of " << length << ": ";
cin >> inputedString;
if(inputedString.size() == length) {
break;
}else {
cout << "Length of the inputed string must be " << length << "!" << endl;
}
}
return inputedString;
}
int searchForTheQuery(string totalPhrase, string queryPhrase) {
for(int i = 0; i < totalPhrase.size(); i++) {
char currentChar = totalPhrase[i];
bool canQueryNextChar = i + 1 < totalPhrase.size();
if(currentChar == queryPhrase[0] && canQueryNextChar && totalPhrase[i + 1] == queryPhrase[1]) {
bool found = true;
for(int j = 0; j < queryPhrase.size(); j++) {
if(totalPhrase[i + j] != queryPhrase[j]) {
found = false;
break;
}
}
if(found) {
return i;
}
}
}
return -1; // not founded
}
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