A commonly used sentence pattern in C + + (two for (;;) The importance of the statement in conjunction)

In some simple C + + programming, there are often two for (;;) Statement with the case, this is a common sentence pattern, so the feeling is also very important. Here are two examples to illustrate:

Example 1. With two for (;;) Statement to sort the size of an array element

#include "stdafx.h"

#include <iostream>

using namespace Std;

int main ()

{

int i,j,t=0;

int a[10]={0};

Enter 10 consecutive numbers in the array with a For loop

for (i=0;i<10;i++)

{

cin>>a[i];

}

Two for loop, sort input values in small to large order

for (i=0;i<10;i++)

for (j=i+1;j<10;j++)

{

if (A[i]>a[j])

{

T=a[i];

A[I]=A[J];

a[j]=t;

}

}

The sorted array values are output in order from small to large in a for loop

for (i=0;i<10;i++)

{

cout<<a[i]<<endl;

}

return 0;

}

Example 2. A corridor is followed by N (1≤n≤65535) lamps, from beginning to end numbered 1, 2, 3 、... n-1, N. Each lamp is controlled by a pull-wire switch. At first, the lights were all closed. There were n students walking through the corridor. The first student pulls the switch of the electric light with a number of multiples of 1, then the second student pulls the switch of the light bulb, which is usually a multiple of 2, and the third student pulls the switch of the electric light with a number of multiples of 3; N students according to the provisions of the walk, there are several lights in the corridor. Note: The number of lights is the same as the number of students.

Program:

#include "stdafx.h"

#include <iostream>

#define MAX 65535

using namespace Std;

int _tmain (int argc, _tchar* argv[])

{

int n, I, j,cnt=0, A[max] = {0};

CIN >> N;

if ((N < 1) | | (N>max))

cout << "Input Error! "<< Endl;

for (i = 1; I <= n; i++)

{

for (j = 1; J <= N; j + +)

{

if ((j%i) = = 0)

{

A[J] + = 1;

A[J]%= 2;

}

}

}

for (i = 1; i<=n; i++)

{

if (a[i]==1)

cnt++;

}

cout << "Number of Lights" << cnt << "Light" << Endl;

return 0;

}

A corridor is followed by a

N (1

≤

N

≤

65535)

Lamp, numbered from beginning to end

1

、

2

、

3

、

... n

-1

、

N

。 Every

The lamp is controlled by a pull-wire switch. At first, the lights were all closed.

Yes

N

A student walked through the corridor. The first student has a number

1

A multiplier of the light switch pull;

A student puts the number

2

A multiple of the light switch pull up; then a third student

3

In multiples of

The switch of the light was pulled;

N

A student puts the number

N

The multiples of the light switch pull

A moment.

N

A student according to the provisions of the Walk, the corridor in the light of several lights.

Note: The number of lights is the same as the number of students.

A commonly used sentence pattern in C + + (two for (;;) The importance of the statement in conjunction)