Reverse int within the 32-bit signed integer range: [−2^31, 2^31 − 1] OptimizedReverse int within the 32-bit signed integer range: $[−2^31, 2^31 − 1]$

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Reverse int within the 32-bit signed integer range: [−2^31, 2^31 − 1] Optimized


Reverse int within the 32-bit signed integer range: $[−2^31, 2^31 − 1]$













0












$begingroup$


Optimized from my original question here. Based on this LeetCode problem.. I'm trying to come up with a good approach that just math operations to iterate a serious of digits using division, almost treating the int like a stack poping using modulus, and pushing using multiplication. I think there still may be some overflow edge cases I am not catching like 1534236469, but need some help coming up with how to detect and prevent such cases.



#include <cassert>
#include <climits>
#include <cmath>
#include <iostream>

class Solution

public:
int reverse(int i) i < INT_MIN)
return 0;

int sign = 1;
if(i < 0)
sign = -1;
i = i*sign;


int reversed = 0;
int pop = 0;

while(i > 0)
pop = i % 10;
reversed = reversed*10 + pop;
i /= 10;


std::cout << reversed << 'n';

return reversed*sign;

;

int main()

Solution s;

assert(s.reverse(1) == 1);
assert(s.reverse(0) == 0);
assert(s.reverse(123) == 321);
assert(s.reverse(120) == 21);
assert(s.reverse(-123) == -321);
assert(s.reverse(1207) == 7021);
assert(s.reverse(1534236469) == 0);
assert(s.reverse(-2147483412) == -2143847412);









share









$endgroup$
















    0












    $begingroup$


    Optimized from my original question here. Based on this LeetCode problem.. I'm trying to come up with a good approach that just math operations to iterate a serious of digits using division, almost treating the int like a stack poping using modulus, and pushing using multiplication. I think there still may be some overflow edge cases I am not catching like 1534236469, but need some help coming up with how to detect and prevent such cases.



    #include <cassert>
    #include <climits>
    #include <cmath>
    #include <iostream>

    class Solution

    public:
    int reverse(int i) i < INT_MIN)
    return 0;

    int sign = 1;
    if(i < 0)
    sign = -1;
    i = i*sign;


    int reversed = 0;
    int pop = 0;

    while(i > 0)
    pop = i % 10;
    reversed = reversed*10 + pop;
    i /= 10;


    std::cout << reversed << 'n';

    return reversed*sign;

    ;

    int main()

    Solution s;

    assert(s.reverse(1) == 1);
    assert(s.reverse(0) == 0);
    assert(s.reverse(123) == 321);
    assert(s.reverse(120) == 21);
    assert(s.reverse(-123) == -321);
    assert(s.reverse(1207) == 7021);
    assert(s.reverse(1534236469) == 0);
    assert(s.reverse(-2147483412) == -2143847412);









    share









    $endgroup$














      0












      0








      0





      $begingroup$


      Optimized from my original question here. Based on this LeetCode problem.. I'm trying to come up with a good approach that just math operations to iterate a serious of digits using division, almost treating the int like a stack poping using modulus, and pushing using multiplication. I think there still may be some overflow edge cases I am not catching like 1534236469, but need some help coming up with how to detect and prevent such cases.



      #include <cassert>
      #include <climits>
      #include <cmath>
      #include <iostream>

      class Solution

      public:
      int reverse(int i) i < INT_MIN)
      return 0;

      int sign = 1;
      if(i < 0)
      sign = -1;
      i = i*sign;


      int reversed = 0;
      int pop = 0;

      while(i > 0)
      pop = i % 10;
      reversed = reversed*10 + pop;
      i /= 10;


      std::cout << reversed << 'n';

      return reversed*sign;

      ;

      int main()

      Solution s;

      assert(s.reverse(1) == 1);
      assert(s.reverse(0) == 0);
      assert(s.reverse(123) == 321);
      assert(s.reverse(120) == 21);
      assert(s.reverse(-123) == -321);
      assert(s.reverse(1207) == 7021);
      assert(s.reverse(1534236469) == 0);
      assert(s.reverse(-2147483412) == -2143847412);









      share









      $endgroup$




      Optimized from my original question here. Based on this LeetCode problem.. I'm trying to come up with a good approach that just math operations to iterate a serious of digits using division, almost treating the int like a stack poping using modulus, and pushing using multiplication. I think there still may be some overflow edge cases I am not catching like 1534236469, but need some help coming up with how to detect and prevent such cases.



      #include <cassert>
      #include <climits>
      #include <cmath>
      #include <iostream>

      class Solution

      public:
      int reverse(int i) i < INT_MIN)
      return 0;

      int sign = 1;
      if(i < 0)
      sign = -1;
      i = i*sign;


      int reversed = 0;
      int pop = 0;

      while(i > 0)
      pop = i % 10;
      reversed = reversed*10 + pop;
      i /= 10;


      std::cout << reversed << 'n';

      return reversed*sign;

      ;

      int main()

      Solution s;

      assert(s.reverse(1) == 1);
      assert(s.reverse(0) == 0);
      assert(s.reverse(123) == 321);
      assert(s.reverse(120) == 21);
      assert(s.reverse(-123) == -321);
      assert(s.reverse(1207) == 7021);
      assert(s.reverse(1534236469) == 0);
      assert(s.reverse(-2147483412) == -2143847412);







      c++ mathematics integer





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      greggreg

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