Where can I use OpenMP in my C++ code - c++

Question

I am writing a C++ code to calculate the code coverage and I want to used the OpenMP to help enhance my code by minimizing the overall run time by making the functions work in parallel so I can get less run time.
Can someone please tell me how and where to use the OpenMP?
int _tmain(int argc, _TCHAR* argv[])
{
std::clock_t start;
start = std::clock();
char inputFilename[] = "Test-Case-3.cs"; // Test Case File
char outputFilename[] = "Result.txt"; // Result File
int totalNumberOfLines = 0;
int numberOfBranches = 0;
int statementsCovered = 0;
float statementCoveragePercentage = 0;
double overallRuntime = 0;
ifstream inFile; // object for reading from a file
ofstream outFile; // object for writing to a file
inFile.open(inputFilename, ios::in);
if (!inFile) {
cerr << "Can't open input file " << inputFilename << endl;
exit(1);
}
totalNumberOfLines = NoOfLines(inFile);
inFile.clear(); // reset
inFile.seekg(0, ios::beg);
numberOfBranches = NoOfBranches(inFile);
inFile.close();
statementsCovered = totalNumberOfLines - numberOfBranches;
statementCoveragePercentage = (float)statementsCovered * 100/ totalNumberOfLines;
outFile.open(outputFilename, ios::out);
if (!outFile) {
cerr << "Can't open output file " << outputFilename << endl;
exit(1);
}
outFile << "Total Number of Lines" << " : " << totalNumberOfLines << endl;
outFile << "Number of Branches" << " : " << numberOfBranches << endl;
outFile << "Statements Covered" << " : " << statementsCovered << endl;
outFile << "Statement Coverage Percentage" << " : " << statementCoveragePercentage <<"%"<< endl;
overallRuntime = (std::clock() - start) / (double)CLOCKS_PER_SEC;
outFile << "Overall Runtime" << " : " << overallRuntime << " Seconds"<< endl;
outFile.close();
}
i want to minimize the time taken to count the number of branches by allowing multiple threads to work in parallel to calculate the number faster? how can i edit the code so that i can use the open mp and here you can find my functions:bool is_only_ascii_whitespace(const std::string& str)
{
auto it = str.begin();
do {
if (it == str.end()) return true;
} while (*it >= 0 && *it <= 0x7f && std::isspace(*(it++)));
// one of these conditions will be optimized away by the compiler,
// which one depends on whether char is signed or not
return false;
}
// Function 1
int NoOfLines(ifstream& inFile)
{
//char line[1000];
string line;
int lines = 0;
while (!inFile.eof()) {
getline(inFile, line);
//cout << line << endl;
if ((line.find("//") == std::string::npos)) // Remove Comments
{
if (!is_only_ascii_whitespace(line)) // Remove Blank
{
lines++;
}
}
//cout << line << "~" <<endl;
}
return lines;
}
// Function 2
int NoOfBranches(ifstream& inFile)
{
//char line[1000];
string line;
int branches = 0;
while (!inFile.eof()) {
getline(inFile, line);
if ((line.find("if") != std::string::npos) || (line.find("else") != std::string::npos))
{
branches++;
}
}
return branches;
}