BUCHAREST - The 59th edition of the International Mathematical Olympiad (IMO) kicked off on Sunday in the western city of Cluj-Napoca, gathering more than 600 best high school students in mathematics worldwide.

British mathematician Geoff Smith, president of the IMO board, told the opening that Romania is the motherland of the International Mathematical Olympiad, as the country has initiated and organized the first edition in 1959.

"As a good child, it must visit its parents," the 65-year-old mathematician said humorously, stressing that the event is a unique experience and a rare opportunity to link friendships and explore the relationship with extraordinary people all over the world.

Attending the opening ceremony, Romanian President Klaus Iohannis underscored that it's an honor for the country to have the opportunity to prove to the entire world its commitment and openness towards knowledge, science and international cooperation in the year when Romania celebrates the centennial of national unity.

"The best way to celebrate the great successes of the past is to build a solid future for the younger generations. There isn't a more suitable way to do this thing than to invest in education, cross-border cooperation and sustainable development," he said, hoping that Romania becomes an attractive destination for the research in the area of mathematics and science.

IMO is the largest, oldest and most prestigious scientific Olympiad for high school students. The history of IMO dates back to 1959, when the first edition was held in Brasov, central Romania, with seven countries participating: Romania, Hungary, Bulgaria, Poland, Czechoslovakia, East Germany, and USSR.

This year, Romania hosts for the 6th time the event. It's noteworthy that Romania and Bulgaria are the only countries to have participated uninterruptedly in all the editions.

According to the competition rules, each country can send a team of up to six secondary students or individuals who have not entered University or the equivalent, as of the date of celebration of the Olympiad. During the competition, contestants have to solve, individually, two contest papers on two consecutive days, with three problems each day.

As a powerful force in the mathematics Olympiad, China's mainland has sent a competition team composed of six students.

The Olympiad will be concluded on July 13 and a award ceremony will be held.