《Cracking the Coding Interview》——第17章：普通题——题目5

2014-04-28 22:44

题目：猜数字游戏。四个数字，每个都是0~9之间。你每猜一次，我都告诉你，有多少个位置和数字都对（全对），有多少个位置错数字对（半对）。比如“6309”，你猜“3701”，就有1全对，1半对。

解法：依照题意写就可以了。

代码：

 1 // 17.5 I am the Master Mind. Guess the number.

 2 // When you guessed the right number at the right position, you got a hit.

 3 // When you guessed the right number at the wrong position, you got a pseudo-hit.

 4 #include <cstdio>

 5 using namespace std;

 6 

 7 void check(int solution[], int guess[], int &hit, int &pseudo_hit)

 8 {

 9     static int c[4];

10     static int mark[4];

11     

12     int i;

13     for (i = 0; i < 4; ++i) {

14         c[i] = 0;

15         mark[i] = 0;

16     }

17     

18     hit = pseudo_hit = 0;

19     for (i = 0; i < 4; ++i) {

20         if (solution[i] == guess[i]) {

21             // hit

22             mark[i] = 1;

23             ++hit;

24         } else {

25             ++c[solution[i]];

26         }

27     }

28     for (i = 0; i < 4; ++i) {

29         if (mark[i]) {

30             continue;

31         }

32         // pseudo_hit

33         if (c[guess[i]] > 0) {

34             mark[i] = 2;

35             --c[guess[i]];

36             ++pseudo_hit;

37         }

38     }

39 }

40 

41 int main()

42 {

43     int solution[4];

44     int guess[4];

45     int hit, pseudo_hit;

46     int i;

47     

48     while (scanf("%d", &solution[0]) == 1) {

49         for (i = 1; i < 4; ++i) {

50             scanf("%d", &solution[i]);

51         }

52         for (i = 0; i < 4; ++i) {

53             scanf("%d", &guess[i]);

54         }

55         check(solution, guess, hit, pseudo_hit);

56         printf("%d hit(s), %d pseudo-hit(s).\n", hit, pseudo_hit);

57     }

58     

59     return 0;

60 }