Why the two declaration is different [duplicate]

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• Why are these constructs (using ++) undefined behavior? 8 answers

    #include<stdio.h>
    #include<conio.h>
    main()
    {
    clrscr();
    int i=2,int j;
    j=i++ + i++ + ++i + i++ + i++ + i++ + ++i;
    printf("%d %d",j,i);    
    getch();  
    }
    main()
    {
    clrscr();
    int i=2;
    int j=i++ + i++ + ++i + i++ + i++ + i++ + ++i;
    printf("%d %d",j,i);    
    getch();  
    }

Consider the above code i have declared j then use it in the expression but if i declared j inline the output changes .in both the above case turbo c++ 3.0 compiler gives different result why??please explain