Some projects--mourning the 512 Wenchuan earthquake--The old man is really hungry.

For survivors of the disaster, the most urgent is to solve the problem of food and clothing, the relief forces on the one side of the organization to get through the traffic, while organizing the procurement of grain. Now assume that a certain amount of relief funds to go to the market to buy rice (in bulk). If the market has m species of rice, the price and weight of various rice is known, ask, in order to meet the needs of more victims, the maximum amount of rice can be purchased?
Input data first contains a positive integer c, which indicates that there is a C set of test cases, the first line of each set of test cases is two integers n and m (0<n<=1000,0<m<=1000), respectively, the amount of funds and the type of rice, then the M row of data, Each line contains 2 integers p and h (1<=p<=25,1<=h<=100), each representing the unit price and the weight of the corresponding rice. Output for each set of test data, export the maximum weight that can be purchased for rice (you can assume that you are buying not just all of the rice).
The output of each instance occupies one row, leaving 2 decimal places. Sample Input

17 23 34 4

Sample Output

2.33

Idea: The unit price is sorted first, if the same row quantity, the total price of each kind of rice will be calculated, if less than the budget cycle continues, greater than the budget minus the excess portion, the end of the cycle.

Code

#include <iostream> #include <algorithm> #include <cstdio>using namespace std;struct intn{int p,h;} D[1100];bool CMP (INTN a,intn b) {if (A.P==B.P) return A.h>b.h;return A.P<B.P;} int main () {int c,n,m,i,money;double sum;while (cin>>c) {while (c--) {  cin>>n>>m;  for (i=0;i<m;i++)  cin>>d[i].p>>d[i].h;  Sort (d,d+m,cmp);  sum=0;  money=0;  for (i=0;i<m;i++)  {money+=d[i].p*d[i].h; sum+=d[i].h; if (money>n) {sum-= (money-n) * (double) 1/d[i].p;break ; }  }  printf ("%.2lf\n", Sum);}} return 0;}

Some projects--mourning the 512 Wenchuan earthquake--The old man is really hungry.