How Can You Print Numbers 1 to 1000 in C Without Loops or Conditional Statements?

Printing 1 to 1000 without Looping or Conditional Statements

In the world of programming, it can be challenging to accomplish seemingly simple tasks without using conventional loop or conditional syntax. One such task is printing a series of numbers from 1 to 1000.

Compilation into Conditional-Free Assembly

A clever solution involves compiling a code snippet into assembly instructions that lack conditionals. Consider the following C code:

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

void main(int j) {
  printf("%d\n", j);
  (&&main + (&&exit - &&main)*(j/1000))(j+1);
}

This code utilizes the "&&" operators to cast function pointers and calculate an offset based on the division result of "j/1000." By chaining the function calls, it effectively prints the sequence of numbers without loops or conditions.

An Alternative Approach with Function Pointers

An alternative solution adheres to standard C and doesn't rely on function pointer arithmetic:

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

void f(int j)
{
    static void (*const ft[2])(int) = { f, exit };

    printf("%d\n", j);
    ft[j/1000](j + 1);
}

int main(int argc, char *argv[])
{
    f(1);
}

This code employs a static array of function pointers to achieve the same result as the previous example. By dynamically selecting and calling these functions, it avoids the use of conditionals or loops.

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