// Interview question 61: Straight of playing cards /// Title: Randomly draw 5 cards from the playing cards to determine whether it is a straight, that is, whether the 5 cards are continuous. // 2 to 10 are the numbers themselves, A is 1, J is 11, Q is 12, K is 13, and big and small kings can be regarded as arbitrary numbers. #include <cstdio> #include <cstdlib> int Compare ( const void * arg1, const void * arg2); bool IsContinuous ( int * numbers, int length) { if (numbers == nullptr || length < 0 ) return false ; qsort (numbers, length, sizeof ( int ), Compare); int numberOfZero = 0 ; // Number of size kings for ( int i = 0 ; i <length && numbers [i] == 0 ; i ++ ) ++ numberOfZero; // Forget that for loop can have multiple conditions int numberOfGap = 0 ; for ( int i = numberOfZero; i <length- 1 ; i ++) // Start with the first number that is not 0 { if (numbers [i + 1 ] == numbers [i]) // If there is a pair, then It can't be a straight return false ; numberOfGap + = (numbers (i +1] - numbers[i] - 1); //差2 == 间隙1 } return (numberOfZero >= numberOfGap) ? true : false; } int Compare(const void* arg1, const void* arg2) { return *(int*) arg1 - *(int*) arg2; }
// ====================测试代码==================== void Test(const char* testName, int* numbers, int length, bool expected) { if (testName != nullptr) printf("%s begins: ", testName); if (IsContinuous(numbers, length) == expected) printf("Passed.\n"); else printf("Failed.\n"); } void Test1() { int numbers[] = { 1, 3, 2, 5, 4 }; Test("Test1", numbers, sizeof(numbers) / sizeof(int), true); } void Test2() { int numbers[] = { 1, 3, 2, 6, 4 }; Test("Test2", numbers, sizeof(numbers) / sizeof(int), false); } void Test3() { int numbers[] = { 0, 3, 2, 6, 4 }; Test("Test3", numbers, sizeof(numbers) / sizeof(int), true); } void Test4() { int numbers[] = { 0, 3, 1, 6, 4 }; Test("Test4", numbers, sizeof(numbers) / sizeof(int), false); } void Test5() { int numbers[] = { 1, 3, 0, 5, 0 }; Test("Test5", numbers, sizeof(numbers) / sizeof(int), true); } void Test6() { int numbers[] = { 1, 3, 0, 7, 0 }; Test("Test6", numbers, sizeof(numbers) / sizeof(int), false); } void Test7() { int numbers[] = { 1, 0, 0, 5, 0 }; Test("Test7", numbers, sizeof(numbers) / sizeof(int), true); } void Test8() { int numbers[] = { 1, 0, 0, 7, 0 }; Test("Test8", numbers, sizeof(numbers) / sizeof(int), false); } void Test9() { int numbers[] = { 3, 0, 0, 0, 0 }; Test("Test9", numbers, sizeof(numbers) / sizeof(int), true); } void Test10() { int numbers[] = { 0, 0, 0, 0, 0 }; Test("Test10", numbers, sizeof(numbers) / sizeof(int), true); } // 有对子 void Test11() { int numbers[] = { 1, 0, 0, 1, 0 }; Test("Test11", numbers, sizeof(numbers) / sizeof(int), false); } // 鲁棒性测试 void Test12() { Test("Test12", nullptr, 0, false); } int main(int argc, char* argv[]) { Test1(); Test2(); Test3(); Test4(); Test5(); Test6(); Test7(); Test8(); Test9(); Test10(); Test11(); Test12(); return 0; }
Analysis: It's really simple after modeling.
class Solution { public: bool IsContinuous( vector<int> numbers ) { int length = numbers.size(); if (length < 1) return false; sort(numbers.begin(), numbers.end()); int numberOfZero = 0; for (int i = 0; i < length && numbers[i] == 0; ++i) ++numberOfZero; int numberOfGap = 0; for (int i = numberOfZero; i < length - 1; ++i) { if (numbers[i + 1] == numbers[i]) return false; numberOfGap += (numbers[i + 1] - numbers[i] - 1); } return (numberOfZero >= numberOfGap)? true:false; } };