The analysis of pointer reference and time-space complexity

Analysis of time-space complexity:

Sacrifice time in exchange for space, or sacrifice space for time:
If the space is very large, you can use multi-threading, can greatly speed up
If the space is small and only one element is used, this increases the time

Use XOR ^ without the help of intermediate variables to achieve the exchange of data a^=b
To complete the interchange between the two arrays, using an array to swap as a temporary intermediate variable, you can use multithreading,
Compared to using only one data as a temporary variable, greatly speed up the speed, multithreading can be processed in parallel,
O (n) speeds up compared to O (1) and O (1) Saves space compared to O (n)
With xor ^ a^=b is O (0) Save time and save space
XOR Exchange: (*P1) ^= (*P2);
(*P2) ^= (*P1);
(*P1) ^= (*P2);

#include <iostream>
#include <time.h>

using namespace Std;

In general, look at the time of an algorithm to see the cycle, look at the space to see how much memory saved
void search (int *p,int n,int data)
{

for (int i = 0; i < n;i++)//Cycle count time
{
if (P[i]==data)
{
Return
}
}
}
void swap (int *p1,int *p2)
{
(*P1) ^= (*P2);
(*P2) ^= (*P1); /* With Xor ^ a^=b is O (0) Save time and save space */
(*P1) ^= (*P2);

{
int temp = *P1;
*P1 = *P2; With the middle variable speed will be very slow to change space with time
*P2 = temp;
}

}

void Main ()
{
time_t ts;
unsigned int times = time (&ts);
Srand (times);

int a[100];
for (int i = 0; i < 100;i++)
{
cout << (A[i] = rand ()) << Endl;
}
unsigned short data = 65535;
Data + = 1, fault tolerance, can be handled in any situation
printf ("Brother Fei has%d", data);

Cin.get ();
}

How to index:
Compared to arrays: compared to chained storage:
n indexes, m elements n indexes, M elements
Delete Order find binary lookup linked list lookup: O (M) index O (m/n)
Array index array index array index list insert: O (1) index O (1)
O (M) O (m/n) O (M) O (m/n) increased deletion of O (N) O (m/n) linked list: 0 (1) index O (1)
Added list: O (1) index O (1)

Finally, we share two little perverted interview questions:

1. Int (*z (int x,int (*y) (int))) (int)
Analysis:
The prototype is: Int (*t) (int)
Int (*y) (int) =y function pointer
1 can be abbreviated as: Y z (int x, y)
Z is a function whose argument is a function pointer return value is also a function pointer

2. Int (*&z (int x,int (*&y) (int))) (int)
&z a reference to a function pointer whose argument is a reference to a function pointer that returns a reference to a function pointer

The analysis of pointer reference and time-space complexity