sentence check

Bjarne Stroustrup “Programming Principles and Practice Using C++”
Chapter 6 Exercise 6
Using std_lib_facilities.h by Bjarne Stroustrup.

[code language=”cpp”]
// Philipp Siedler
// Bjarne Stroustrup’s PP
// Chapter 6 Exercise 6

/*
input:
birds fly and fish swim.
C++ rules.
x
*/

#include "std_lib_facilities.h"

//word vector setup
vector<string> nouns;
vector<string> verbs;
vector<string> conjunctions;

//initialize word vectors
void init(){
nouns.push_back("birds");
nouns.push_back("fish");
nouns.push_back("C++");

verbs.push_back("rules");
verbs.push_back("fly");
verbs.push_back("swim");

conjunctions.push_back("and");
conjunctions.push_back("or");
conjunctions.push_back("but");
}

bool isNounString(string w) {
for (int i = 0; i < nouns.size(); i++) {
if (w == nouns[i]) {
return true;
}
}
return false;
}

bool isVerbString(string w) {
for (int i = 0; i < verbs.size(); i++) {
if (w == verbs[i]) {
return true;
}
}
return false;
}

bool isConjunctionString(string w) {
for (int i = 0; i < conjunctions.size(); i++) {
if (w == conjunctions[i]) {
return true;
}
}
return false;
}

bool sentences() {
string w;
cin >> w;
if (!isNounString(w)) {
return false;
}

string w1;
cin >> w1;
if (!isVerbString(w1)) {
if (w1[w1.size() – 1] == ‘.’) {
return true;
}
else {
return false;
}
}

string w2;
cin >> w2;
if (!isConjunctionString(w2)) {
return false;
}
return sentences();
}

int main()
try
{
init();
cout << "Enter sentece to be checked or x to exit:\n";

while (true) {
char exit;
if (cin >> exit && exit == ‘x’) {
break;
}
else {
cin.putback(exit);
bool check = sentences();
if (check) {
cout << "OK!\n";
cout << "x for exit or continue:" << endl;
}
else {
cout << "Not OK!\n";
cout << "Try again:\n";
}
}

}

/*
while (cin) {

}
*/

keep_window_open(".");
}

catch (runtime_error e) {
cout << e.what() << "\n";
keep_window_open(".");
}
catch (…) {
cout << "Exiting!\n";
keep_window_open(".");
}
[/code]

Output:
Enter sentece to be checked or x to exit:
birds fly and fish swim.
OK!
x for exit or continue:
C++ rules.
OK!
x for exit or continue:
x
Please enter . to exit