a question regarding to std vector

[laephy]

I have a vector defined as follows

 vector<wstring> m_vInfo;

which contains information about the calculation. For each calculation iteration, an element is added to the vector through the function push_back. These elements can contain both strings "completed calculation" or "error during calculation".

 m_vInfo = {completed calculation, error during calculation, completed calculation, completed, completed calculation, error during calculation, ..................}

My question is if there is a function to know if an element contains for example the word completed or not?

Thanks

[2kaud]

Yes, as an example consider

#include <vector>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;

int main()
{
const string tofind{ "completed" };
const vector<string> vs{ "error during calculation", "completed calculation", "calculation", "error during calculation" };

	cout << "Does" << ((find_if(vs.begin(), vs.end(), [&tofind](string elem){return elem.find(tofind) != string::npos; }) == vs.end()) ? " not" : "") << " contain " << tofind << endl;
}

[superbonzo]

FYI, c++11 added std::any_of to replace the more verbose std::find_if() != .end()

[tiliavirga]

My question is if there is a function to know if an element contains for example the word completed or not?

I think you should consider it a two-stage problem.

1. The first problem is to visit each element of the vector.

2. The second problem is to find out something about each element.

If you separate your code in this way you have the most options available to you. Both stages can be performed using available library functions or higher level language constructs.

For example you can do the visiting (1) in parallel utilizing all cores of the computer. If this is done in a performance bottleneck it may greatly improve the throughtput of your program.

[PredicateNormative]

Learning aside, perhaps the wrong tool for the job is being used in your here. If the only two options are that the task passed or that it failed, then wouldn't a container of boolean values (e.g. deque<bool> to avoid the bad vector<bool> specialisation) be a better option here (e.g. completed = true, failed = false)? Else if more than two options are possible then a vector of enumerations would be better. Just my two cents.