"Leetcode-Interview algorithm classic-java Implementation" "029-divide two integers (divide two integers)"

"029-divide two integers (divide two integers)" "leetcode-Interview algorithm classic-java Implementation" "All topics Directory Index" Original Question

Divide-integers without using multiplication, division and mod operator.
If It is overflow, return max_int.

Main Topic

The result of dividing two integers without using division, multiplication, and taking, returns the largest integer if there is an overflow.

Thinking of solving problems

Any integer can be represented as a linear combination of a set of bases at the base of a power of 2, namely num=a_0*2^0+a_1*2^1+a_2*2^2+...+a_n*2^n. Based on the above formula and the shift left one is equivalent to multiplying by 2, we first let the divisor shift left until it is greater than dividend to get a maximum base. Then each time we try to subtract the base, if we can add 2^k to the result, then the base continues to move the iteration right until the base is 0. The time complexity is O (log (n)) because the iteration number of this method is known to exceed the result by a power of 2.

Code Implementation

Algorithm implementation class

 Public classSolution { Public int Divide(intDividend,intDivisor) {//Divide overflow handling        if(Divisor = =0|| Dividend = = Integer.min_value && divisor = =-1) {returnInteger.max_value; }//Find sign bit        intSign = ((Dividend <0) ^ (Divisor <0)) ? -1:1;//Seek absolute value, to prevent overflow using long        LongDVD = Math.Abs ((Long) dividend);LongDVS = Math.Abs ((Long) divisor);//Record results        intresult =0;//dividend greater than divisor         while(DVD >= DVS) {//Record divisor            LongTMP = DVS;//size of the logger            LongMul =1; while(DVD >= (TMP <<1) {tmp <<=1; Mul <<=1; }//Subtract the value of the index times of the DVS closest to the DVD (value tmp)DVD-= TMP;//Correction Resultsresult + = Mul; }returnresult * SIGN; }}

Evaluation Results

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"Leetcode-Interview algorithm classic-java Implementation" "029-divide two integers (divide two integers)"