C/C++ printf() before scanf() issue

Your output is being buffered.
You have 4 options:

  1. explicit flush

    fflush after each write to profit from the buffer and still enforce the desiredbehavior/display explicitly.

     fflush( stdout );
    
  2. have the buffer only buffer lines-wise

    useful for when you know that it is enough to print only complete lines

     setlinebuf(stdout);
    
  3. disable the buffer

     setbuf(stdout, NULL);
    
  4. disable buffering in your console through what ever options menu it provides


Examples:

Here is your code with option 1:

#include <stdio.h>
int main() {

    int myvariable;
    
    printf("Enter a number:");
    fflush( stdout );
    scanf("%d", &myvariable);
    printf("%d", myvariable);
    fflush( stdout );

    return 0;
}

Here is 2:

#include <stdio.h>
int main() {

    int myvariable;

    setlinebuf(stdout);    

    printf("Enter a number:");
    scanf("%d", &myvariable);
    printf("%d", myvariable);

    return 0;
}

and 3:

#include <stdio.h>
int main() {

    int myvariable;

    setbuf(stdout, NULL);     

    printf("Enter a number:");
    scanf("%d", &myvariable);
    printf("%d", myvariable);

    return 0;
}

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