If you have written some tasks, and have prepared test cases, you will probably experience the terrible feeling that some test cases may be invalid (meaning it does not agree with the constraints in problem statement): upper bound can be violated, your graph not satisfied connectivity requirements or is not at tree. It is a reasonable to feel that way. Even experienced problem setters make mistakes sometimes (for example, in the pretigious ACM ICPC World final 2007).

The validator in testlib is a good tool to help you prevent such mistakes. It is very easy to use.

Example

Following is the validator of validator, which I used in a problem I prepared: 100541A - Stock Market:

#include "testlib.h"
#include <bits/stdc++.h>
using namespace std;

int main() {
    registerValidation();
    int test = inf.readInt(1, 10);
    inf.readEoln();
    
    while (test--) {
        int n = inf.readInt(1, 100);
        inf.readChar(' ');
        int w = inf.readInt(1, 1000000);
        inf.readEoln();

        for(int i = 0; i < n; ++i) {
            inf.readInt(1, 1000);
            if (i < n-1) inf.readChar(' ');
            else inf.readEoln();
        }
    }

    inf.readEof();
    return 0;
}

More examples can be found at the Github repo

Available methods:

The first line of your code should be registerValidation() which does some magic in the background, so that you can use the necessary methods.

Most methods for validators start with prefix "read" and it does the same thing: moves input stream pointer to next suitable place after reading something. It also detect violations (input does not match what you are trying to read), and then throw error.

Note: Validator is strict. It cares about correct placing of spaces. For exmple, when you're trying to read an integer and the next character is a space (and then an integer), the validator will throw error.

Following is full list of methods available:

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