Gauss, a great German mathematician, why is he so powerful? Because he studied mathematics hard, he became a mathematician. He was also very clever when he was young, and even soon made a difficult problem that others had to do for a long time. This is the story of Gauss's quick calculation.

This story tells that when Gauss was a teenager, his teacher asked us a difficult arithmetic problem:1+2+3+4 ...+99+100 =? When everyone was thinking hard, Gauss gave the answer:1+100 =101; 2+99 = 10 1 ... so there are 5010/kloc-0. Therefore, as long as it is calculated: 50× 10 1, the answer is 5050.

Gauss solved this problem with some skill: add the last number to the first number, and then add the penultimate number to the second number. In this way, you find the pattern. For example: 1+2+3+4...+98+99 =? The first time you look at this question, you will definitely find it difficult, and even do it vertically for a while. However, as long as you master this trick, you can find:1+99 =100; 2+98 = 100 ... finally, you can work out: there are 49 100 and 1 50. In this way, we can get the final formula: 49× 100+50, and the answer is 4950.

? Therefore, when we encounter such a difficult problem in real life, we must find the trick to solve this problem, so that we can do it quickly and accurately!