Simpler way of sorting three numbers

Is there a simpler and better way to solve this problem because

1. I used too many variables.
2. I used so many if else statements
3. I did this using the brute force method

Write a program that receives three integers as input and outputs the numbers in increasing order.

Do not use loop / array.

#include <stdio.h>
main(){
   int no1;
   int no2;
   int no3;
   int sto;
   int hi;
   int lo;

   printf("Enter No. 1: ");
   scanf("%d", &no1);
   printf("Enter No. 2: ");
   scanf("%d", &no2);         
   printf("Enter No. 3: ");
   scanf("%d", &no3);

   if (no1>no2) {   
      sto=no1;    
      lo=no2;   
   } else {
      sto=no2;  
      lo=no1;  
   } 
   if (sto>no3) { 
      hi=sto;    
      if(lo>no3){         
         sto=lo;                
         lo=no3;
      }else {
         sto=no3;      
      }         
   }else hi=no3; 

   print开发者_如何学编程f("LOWEST %d\n", lo);
   printf("MIDDLE %d\n", sto);
   printf("HIGHEST %d\n", hi);  

   getch(); 
}    

---

if (a > c)
   swap(a, c);

if (a > b)
   swap(a, b);

//Now the smallest element is the 1st one. Just check the 2nd and 3rd

if (b > c)
   swap(b, c);

Note: Swap changes the values of two variables.

---

Call the three variables x, y, and z, then:

if (x > y) swap(x, y);
if (y > z) swap(y, z)
if (x > y) swap(x, y);

Writing the swap function is left as an exercise for the reader. Hint: you may have to use pointers.

---

#include <stdio.h>
#define min(a,b) ((a)<(b)?(a):(b))
#define max(a,b) ((a)>(b)?(a):(b))
int main(){
   int a, b, c;
   int hi;
   int lo;

   printf("Enter No. 1: ");
   scanf("%d", &a);
   printf("Enter No. 2: ");
   scanf("%d", &b);         
   printf("Enter No. 3: ");
   scanf("%d", &c);

   lo = min(min(a, b), c);
   hi = max(max(a, b), c);
   printf("LOWEST %d\n", lo);
   printf("MIDDLE %d\n", a+b+c-lo-hi);
   printf("HIGHEST %d\n", hi);  

   getchar(); 
}    

---

If you want to sort the values into new external variables, you can actually do the swaps without temporaries:

void sort(int a, int b, int c, int *min, int *mid, int *max) {
    min = a;
    mid = b;
    max = c;
    if (min > mid) { mid = a; min = b; }
    if (mid > max)
    {
        max = mid;
        mid = c;
        if (min > mid)
        {
            mid = min;
            min = c;
        }
    }
}

This works because the last swap test is really only needed if the second test succeeds (otherwise it will simply be a repetition of the first test, which will fail by definition since we already sorted those variables).

Because of this, we can track the assignments of each of the original variables and avoid swap locals.

---

The following code performs only 2 (best case) to 3 (worst case) conditional tests, with no assignment operations nor any extra variables:

void echo(int _1st, int _2nd, int _3rd) { printf("%d %d %d", _1st, _2nd, _3rd); }
void echoFrom(int pivot, int x, int y) {
    (pivot < y) ? ((x < y) ? echo(pivot, x, y) : echo(pivot, y, x)) : echo(y, pivot, x);
}
void printSorted(int a, int b, int c) { (a < b) ? echoFrom(a, b, c) : echoFrom(b, a, c); }

Basic call (scanf() stuff avoided for simplicity):

int main() {
    printSorted(2,3,1); //Output: 1 2 3
}

---

To find the min, mid and max of 3 values, you can use the ternary operator. You can either do all your work within the main body of your code, or you can separate the minof3, midof3 and maxof3 calculations into reusable functions.

In the case of min and max you simply make 2 out of 3 possible comparisons, and then return a comparison of the results. In the case of mid, you do the same, but compute the min and max of the 3 values, and then check all 3 against min and max in order to find the value that is neither the min or max. (you can do this part in the main body of your code without an additional function by declaring the min and max values as variables and doing the elimination there).

Putting the pieces together, you could do something similar to the following, which takes the first 3 arguments as the values to sort (or uses defaults of 99, 231, 8 if a needed value isn't specified)

#include <stdio.h>
#include <stdlib.h>

/** direct ternary comparison of 3 values */
long minof3 (long a, long b, long c) {
    long x = a < b ? a : b,
         y = a < c ? a : c;
    return x < y ? x : y;
}

long maxof3 (long a, long b, long c) {
    long x = a > b ? a : b,
         y = a > c ? a : c;
    return x > y ? x : y;
}

long midof3 (long a, long b, long c) {
    long x = a < b ? a : b,
         y = a > b ? a : b,
         z = y < c ? y : c;
    return x > z ? x : z;
}

int main (int argc, char **argv) {

    long x = argc > 1 ? strtol (argv[1], NULL, 10) : 99,
         y = argc > 2 ? strtol (argv[2], NULL, 10) : 231,
         z = argc > 3 ? strtol (argv[3], NULL, 10) : 8;

    /* strtol validations omitted for brevity */

    printf ("\n sorted values : %ld, %ld, %ld\n",
            minof3 (x, y, z), midof3 (x, y, z), maxof3 (x, y, z));
}

Example Use/Output

$ ./bin/sort3
 sorted values : 8, 99, 231

$ ./bin/sort3 -23 -281 1031
 sorted values : -281, -23, 1031

(yes, I know this is an old post, but given the recent comment about code hidden behind the swap function, a full example was in order).

---

A compact solution sans magic swap() function, that dances around int overflow, and abuses arrays:

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv) {

    int a = atoi(argv[1]);
    int b = atoi(argv[2]);
    int c = atoi(argv[3]);

    int ab[] = {a, b}, bc[] = {b, c};
    int smaller[] = {ab[a > b], bc[b > c]}, larger[] = {ab[a < b], bc[b < c]};
    int smallest = smaller[a > c], largest = larger[a < c];
    int middle = (a - smallest) + (b - largest) + c;

    printf("%d, %d, %d\n", smallest, middle, largest);

    return 0;
}

USAGE

> ./a.out 2147483647 2147483645 2147483646
2147483645, 2147483646, 2147483647
> 

---

#include <stdio.h>
int main()
{
  int a;
  int b;
  int c;

  //Temporary storage variable
  int t = 0;

  printf("Enter No. a: ");
  scanf("%d", &a);
  printf("Enter No. b: ");
  scanf("%d", &b);         
  printf("Enter No. c: ");
  scanf("%d", &c);

  if (a > b) 
  {   
      t = a;    
      a = b;
      b = t;
  }
  if (a > c)
  {
    t = a;
    a = c;
    c = t;
  }
  if (c < b)
  {
    t = c;
    c = b;
    b = t;
  }
  
  printf("a = %d < b = %d < c = %d", a, b, c);
  
  return 0;
}

---

#include <stdio.h>

int main() {
    int a,b,c;
    printf("enter a b c values:\n");
    scanf("%d%d%d",&a,&b,&c);
    if(a<b && a<c)
    {   printf("%d,",a);
        if(b<c)
            printf("%d,%d",b,c);
        else
            printf("%d,%d",c,b);
    }
    else if(b<a && b<c)
    {
        printf("%d,",b);
        if(a<c)
            printf("%d,%d",a,c);
        else
        printf("%d,%d",c,a);
    }
    else
    {
    printf("%d,",c);
    if(a<b)
    printf("%d,%d",a,b);
    else
    printf("%d,%d",b,a);
    }
    return 0;
}

---

        int number1 = int.Parse(Console.ReadLine());

        int number2 = int.Parse(Console.ReadLine());

        int number3 = int.Parse(Console.ReadLine());

        int swap = 0;

        if (number2 > number1 && number2 > number3)
        {
            swap = number2;
            number2 = number1;
            number1 = swap;

        }
        else if (number3 > number2 && number3 > number1)
        {
            swap = number3;
            number3 = number1;
            number1 = swap;
        }
        if (number3 > number2)
        {
            swap = number2;
            number2 = number3;
            number3 = swap;

        }
        Console.WriteLine(number1 + "/" + number2 + "/" + number3);
        Console.ReadKey();

---

I was attempting to solve the same problem today. Could make this compact version of code without using any temporary variables; loops; library functions like swap, sort, max, min, etc. The code uses only if statements and makes continuous mutations in the hierarchy until all possibilities are checked.

int main()
{
  int a, b, c; //User inputs stored in these three variables
  int first, second, third; //These three variables will store the sorted numbers in sequence
  std::cout<<"Please enter three integers : "; //User input prompt
  std::cin>>a>>b>>c;

  first = a; //Initially assuming number 'a' is smallest
  if (b <= a && b <= c) first = b; //Checking whether b is smallest
  if (c <= a && c <= b) first = c; //Checking whether c is smallest
  if (((a >= b && a <= c) || (a >= c && a <= b))) second = a; //Checking if a is middle number
  if (((b >= a && b <= c) || (b >= c && b <= a))) second = b; //Checking if b is middle number
  if (((c >= a && c <= b) || (c >= b && b <= a))) second = c; //Checking if c is middle number
  if (a >= b && a >= c) third = a; //Checking if a is the greatest
  if (b >= c && b >= a) third = b; //Checking if b is the greatest
  if (c >= a && c >= b) third = c; //Checking if c is the greatest

  std::cout<<"The numbers in ascending order are : "<<first<<", "<<second<<", "<<third<<std::endl;
}