How to find the second largest number in an array

1. The easiest way to think

We can use the simplest way to find an array of arbitrary size of the number, that is, according to a sort of array of all the elements of the order, and then as needed to remove it, the knowledge of this way of time complexity and space complexity is relatively large, so, with the following way

2. By setting two variables to make a judgment

This way you can find the second largest number by scanning the array only once, in the following form: Define two variables: One variable stores the maximum number of arrays, the initial value is the first element of the array, the other variable stores the second largest number, the initial value is the smallest negative integer, and then the array element is traversed. If the value of the array element is larger than the maximum number of variables, the maximum number of updates, and if the value of the array element is smaller than the maximum value, then the second largest number is compared with that number, if it is larger than the second large number, then the second largest number is updated;

How to find the second largest number in an array