Java: Why is the compiler complaining here?

Question

  0          int specialFuncStart;
  1          String[] specialFunctions= {"sum","ddx","integral"};
  2          for(String element: specialFunctions){
  3              specialFuncStart = finalMath.lastIndexOf("sum");
  4          }
  5          while (specialFuncStart != -1) {   code  }

Why line 5does it say that it specialFuncStartmay not be initialized? Lines are final and fixed, so the for loop will always work. Doesn't the compiler know this, or am I missing something? I understand that initialization specialFuncStart = -1;is how to fix it, but why?

Answer 1

You declared it, but you did not initialize it. You need to set the value for it:

int specialFuncStart; // declare
specialFuncStart = 0; // initialize

int specialFuncStart = 0; // both

Your compiler believes that sometimes specialFuncStartit will not be initialized, since the loop forshould not be executed.

Answer 2

, specialFuncStart for, , , 0, .

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specialFuncStart = 0;

Answer 3

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