【HDOJ】2955 Robberies

01背包。将最大金额作为容量v。概率做乘法。

 1 #include <stdio.h>

 2 #include <string.h>

 3

 4 #define mymax(a, b) (a>b) ? a:b

 5

 6 float dp[10005];

 7 int mon[105];

 8 float fs[105];

 9

10 int main() {

11     int case_n;

12     float ff, f;

13     int m, v;

14     int i, j;

15

16     scanf("%d", &case_n);

17

18     while (case_n--) {

19         scanf("%f %d", &ff, &m);

20         v = 0;

21         for (i=1; i<=m; ++i) {

22             scanf("%d %f", &mon[i], &fs[i]);

23             fs[i] = 1 - fs[i];

24             v += mon[i];

25         }

26         ff = 1 - ff;

27         memset(dp, 0, sizeof(dp));

28         dp[0] = 1;

29         for (i=1; i<=m; ++i) {

30             for (j=v; j>=mon[i]; --j) {

31                 dp[j] = mymax(dp[j], dp[j-mon[i]]*fs[i]);

32             }

33             /*

34             for (j=0; j<=v; ++j) {

35                 printf("%f ", dp[j]);

36             }

37             printf("\n");

38             */

39         }

40         for (i=v; i>0; --i)

41             if (dp[i] >= ff)

42                 break;

43         printf("%d\n", i);

44     }

45

46     return 0;

47 }