解决问题之道---try catch

try {

    sentence_1;

    sentence_2;

    .

    .

    .

    sentence_m;   // if this sentence throws a exception ,program will go to catch() location.

 

    .

    .

    sentence_n;

 

 

}

catch()

{

    //printf(xxx) ;  //1.notify  that exception happens. 

    // return  err;  //2. or return an error to caller.

 

}

 

It seems very simple. but some codes just catch excpetions and changes the route of program runing. It jump to catch ().so the exceptions is covered by the catch (){} sentence. I recommend 2 methods to prevent some strange phenomenon.