There was a problem which had been a global challenge for a long time in American Mathematical Society, New York. However, this problem was solved on the year of 1903 by Frank Nelson Cole, a mathematician professor at Columbia University.
Mathematicians greeted his presentation with a standing ovation but Cole shook his head and said, “I’m not that great like you all think. How long do you think it took for me to solve this problem?
“About a week?”
Once again, Cole shook his head.
“Then, did it take you about a month? It cannot be taken more than that, right?”
He made a gentle smile and answered,
“It took three years of Sundays. I’d been only making a little more effort than the others.”