Kurt Peek - 4 months ago 14

C Question

I'm reading the book "Cracking the Coding Interview" which contains several examples of algorithms in C. I'd like to make programs which implement these algorithms and run them as I go along.

One such algorithm is "Min and Max 1" (from the "Big O" chapter):

`int min = Integer.MAX_VALUE;`

int max = Integer.MIN_VALUE;

for (int x : array) {

if (x < min) min = x;

if (x > max) max = x;

}

I've attempted to 'write a program around this' as follows:

`#include<stdio.h>`

int array[5] = [1, 3, 2, 5, 4];

int min = Integer.MAX_VALUE;

int max = Integer.MIN_VALUE;

int main(void):

{

for (int x : array) {

if (x < min) min = x;

if (x > max) max = x;

}

printf("The minimum is %i", min)

printf("The maximum is %i", max)

}

However, if I try to compile and run this I get the

`error: expected identifier before numeric constant int array[5] = [1, 3, 2, 5, 4];`

Answer

What you mean is the following

```
#include <stdio.h>
#include <limits.h>
#define N 5
int main( void )
{
int array[N] = { 1, 3, 2, 5, 4 };
int min = INT_MAX;
int max = INT_MIN;
for ( size_t i = 0; i < N; i++ )
{
if ( array[i] < min ) min = array[i];
if ( max < array[i] ) max = array[i];
}
printf( "The minimum is %i\n", min );
printf( "The maximum is %i\n", max );
return 0;
}
```

The program output is

```
The minimum is 1
The maximum is 5
```

As for your program then it contains invalid constructions according to the C grammar.

In C++ the loop can look the same way as you showed.

```
#include <iostream>
#include <limits>
int main()
{
const size_t N = 5;
int array[N] = { 1, 3, 2, 5, 4 };
int min = std::numeric_limits<int>::max();
int max = std::numeric_limits<int>::min();
for ( int x : array )
{
if ( x < min ) min = x;
if ( max < x ) max = x;
}
std::cout << "The minimum is " << min << std::endl;
std::cout << "The maximum is " << max << std::endl;
return 0;
}
```

Take into account that there is no sense to declare the array like global.

As for the array definition in C then you can define it either like

```
int array[5] = { 1, 3, 2, 5, 4 };
```

(or using some named constant instead of the number 5)

or like

```
int array[] = { 1, 3, 2, 5, 4 };
```

In the last case the number of elements is equal to the number of the initializers. Or even you can use the following initialization

```
int array[] = { [0] = 1, [1] = 3, [2] = 2, [3] = 5, [4] = 4 };
```