[ALGORITHM - ETC] 대칭수 구하는 문제 (십진수,이진수)

1.

십진수-이진수 변환 : string, while문, shift연산

이진수 대칭 확인 : string_front,string_back,string_front.compare(string_back)

#include <iostream> #include <vector> #include <string> #include <windows.h> #include <stdio.h> #define CHECK_TIME_START __int64 freq, start, end; if (QueryPerformanceFrequency((_LARGE_INTEGER*)&freq)) {QueryPerformanceCounter((_LARGE_INTEGER*)&start); #define CHECK_TIME_END(a,b) QueryPerformanceCounter((_LARGE_INTEGER*)&end); a=(float)((double)(end - start)/freq*1000); b=TRUE; } else b=FALSE; using namespace std; int result; string string_original; void decimal_to_binary(int num) { string_original.clear(); while (num != 0) { string_original.push_back((num) & 1); num >>= 1; } } int compare(string num) { string string_front, string_back; string_front = num.substr(0, num.size() / 2); if (num.size() % 2) string_back = num.substr(num.size() / 2 + 1, num.size() - 1); //짝수 else string_back = num.substr(num.size() / 2, num.size() - 1); //홀수 reverse(string_back.begin(), string_back.end()); if (string_front.compare(string_back) != 0) return 1; return 0; } void check_number(string num) { if (compare(num)) return; decimal_to_binary(atoi(num.c_str())); if (compare(string_original)) return; result += atoi(num.c_str()); } int main() { float Time; BOOL err; CHECK_TIME_START; string number; int test_num; test_num = 1000000; result = 0; for (int j = 1; j < test_num + 1; j++) check_number(to_string(j)); cout << result << endl; CHECK_TIME_END(Time, err); if (err) printf("printf() 걸린 시간은.. %8.6f미리세컨입니다.", Time); system("pause"); } //느림

2.

십진수-이진수 변환 : _itoa함수

이진수 대칭 확인 : string_front,string_back,string_front.compare(string_back)

#define _CRT_SECURE_NO_WARNINGS #include <iostream> #include <vector> #include <string> #include <stdlib.h> #include <stdio.h> #include <windows.h> #define CHECK_TIME_START __int64 freq, start, end; if (QueryPerformanceFrequency((_LARGE_INTEGER*)&freq)) {QueryPerformanceCounter((_LARGE_INTEGER*)&start); #define CHECK_TIME_END(a,b) QueryPerformanceCounter((_LARGE_INTEGER*)&end); a=(float)((double)(end - start)/freq*1000); b=TRUE; } else b=FALSE; using namespace std; int result; string string_original; void decimal_to_binary(int num) { string_original.clear(); char original[100]; _itoa(num, original, 2); string_original = string(original); } int compare(string num) { string string_front,string_back; string_front=num.substr(0,num.size() / 2); if(num.size()%2) string_back=num.substr(num.size() / 2+1, num.size()-1); //짝수 else string_back = num.substr(num.size() / 2, num.size() - 1); //홀수 reverse(string_back.begin(), string_back.end()); if (string_front.compare(string_back) != 0) return 1; return 0; } void check_number(string num) { if (compare(num)) return; decimal_to_binary(atoi(num.c_str())); if (compare(string_original)) return; result += atoi(num.c_str()); } int main() { float Time; BOOL err; CHECK_TIME_START; string number; int test_num; test_num = 1000000; result = 0; for (int j = 1; j < test_num + 1; j++) check_number(to_string(j)); cout << result << endl; CHECK_TIME_END(Time, err); if (err) printf("printf() 걸린 시간은.. %8.6f미리세컨입니다.", Time); system("pause"); } //시간이 훨씬 느림

3.

십진수-이진수 변환 : 1번과 동일

이진수 대칭 확인 : string while문

#include <iostream> #include <vector> #include <string> #include <windows.h> #include <stdio.h> #define CHECK_TIME_START __int64 freq, start, end; if (QueryPerformanceFrequency((_LARGE_INTEGER*)&freq)) {QueryPerformanceCounter((_LARGE_INTEGER*)&start); #define CHECK_TIME_END(a,b) QueryPerformanceCounter((_LARGE_INTEGER*)&end); a=(float)((double)(end - start)/freq*1000); b=TRUE; } else b=FALSE; using namespace std; int result; string string_original; void decimal_to_binary(int num) { string_original.clear(); while (num != 0) { string_original.push_back((num) & 1); num >>= 1; } } int compare(string num) { int start_index = 0; int end_index = num.size() - 1; while (start_index <= end_index) { if(num[start_index]!=num[end_index]) return 1; start_index++; end_index--; } return 0; } void check_number(string num) { if (compare(num)) return; decimal_to_binary(atoi(num.c_str())); if (compare(string_original)) return; result += atoi(num.c_str()); } int main() { float Time; BOOL err; CHECK_TIME_START; string number; int test_num; test_num = 1000000; result = 0; for (int j = 1; j < test_num + 1; j++) check_number(to_string(j)); cout << result << endl; CHECK_TIME_END(Time, err); if (err) printf("printf() 걸린 시간은.. %8.6f미리세컨입니다.", Time); system("pause"); } //훨씬빠름

4.

십진수-이진수 변환 : vector

이진수 대칭 확인 : vector while문

#include <iostream> #include <vector> #include <string> #include <windows.h> #include <stdio.h> #define CHECK_TIME_START __int64 freq, start, end; if (QueryPerformanceFrequency((_LARGE_INTEGER*)&freq)) {QueryPerformanceCounter((_LARGE_INTEGER*)&start); #define CHECK_TIME_END(a,b) QueryPerformanceCounter((_LARGE_INTEGER*)&end); a=(float)((double)(end - start)/freq*1000); b=TRUE; } else b=FALSE; using namespace std; int result; vector<int> binary; void decimal_to_binary(int num) { binary.clear(); int index = 1; while (num != 0) { binary.push_back((num) & 1); num >>= index; } reverse(binary.begin(), binary.end()); } void check_number(string num) { binary.clear(); int end_index = num.size() - 1; for (int j = 0; j < num.size() / 2; j++) { if (num[j] == num[end_index]) end_index--; else return; } decimal_to_binary(atoi(num.c_str())); end_index = binary.size() - 1; for (int j = 0; j < binary.size() / 2; j++) { if (binary[j] == binary[end_index]) end_index--; else return; } result += atoi(num.c_str()); } int main() { float Time; BOOL err; CHECK_TIME_START; string number; int test_num; test_num = 1000000; result = 0; for (int j = 1; j < test_num + 1; j++) { check_number(to_string(j)); } cout << result << endl; CHECK_TIME_END(Time, err); if (err) printf("printf() 걸린 시간은.. %8.6f미리세컨입니다.", Time); system("pause"); }