140805summer training .txt

1. scanf ("% s", S );
// For (I = 0; I <11; I ++)
// Scanf ("% d", s [I]);
When entering a number, each number must be separated by a space before the computer can recognize and distinguish.
If 11 consecutive numbers are input, the computer considers them as a number.
Only 1 8 3 3 6 8 6 3 0 9 9 can the computer think that this is 11
Therefore, use a string
2. If the question provides a mathematical formula, ask you to calculate the value of nth item.
For a mathematics that provides an arithmetic formula, timeout and overmemory cannot be avoided without optimization.
This question is obviously a regular-looking question, that is, there is a circular section in the solution of this question.
3. Log Functions
1> function log is based on E, and log10 is based on 10.
2> double log10 (Double X)
That is, the number required is double, and the return value is double.
3> # include <math. h>
4> it can be used to calculate the number of digits of the number X.
4. Int I, J;
Double L;
L = (I * I + J * j + M)/(I * j * 1.0 );
// Divide the integer by the integer, and the result is always an integer, even if the type on the left side is double
// If you want to get a decimal number, you need to convert a certain data in the right side * 1.0 to double type.
5. memset (S, 0, sizeof (s ));
Initializes array s to 0, which is correct
To initialize the array s to 1, use memset (s, 1, sizeof (s); this write is incorrect, because the memset function assigns values by byte.
To initialize the array s to 1, you can only use the for loop or while loop.
6. s [0] = 1, s [1] = 5, s [2] =-1, s [N] = 8;
Fast sorting of S,
Qsort (S, N, sizeof (s [0]), CMP); --- sort from S [0]
If you want to sort data from S [1], how can you write it?
Qsort (S + 1, n-1, sizeof (s [0]), CMP); --- S is not only the array name, but also the first address of the array to be sorted.
--- N is the number of times to be sorted