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: $[−2^31, 2^31 − 1]$
$begingroup$
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);
c++ mathematics integer
$endgroup$
add a comment |
$begingroup$
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);
c++ mathematics integer
$endgroup$
add a comment |
$begingroup$
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);
c++ mathematics integer
$endgroup$
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
c++ mathematics integer
asked 20 secs ago
greggreg
38218
38218
add a comment |
add a comment |
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