buy-and-sell-n-times/src/test/java/SolutionTest.java

import com.github.stefanbirkner.systemlambda.SystemLambda;
import org.apache.commons.lang3.StringUtils;
import org.junit.jupiter.api.extension.ExtendWith;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.CsvFileSource;

import static org.junit.jupiter.api.Assertions.*;

@ExtendWith( BenchmarkExtension.class )
class SolutionTest {
    
    @ParameterizedTest
    @CsvFileSource( resources = "testdata.csv" )
    void main( final String sellCount, final String input, final String expected ) throws Exception {
        String output = SystemLambda.tapSystemOutNormalized( () -> 
            SystemLambda.withTextFromSystemIn( sellCount + " " + input )
                        .execute( () -> Solution.main( new String[0] ))
        );
        
        assertEquals( expected, StringUtils.chomp( output.trim() ));
    }
    
}