A：hdu5982：

Relic Discovery

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 830    Accepted Submission(s): 661


Problem Description Recently, paleoanthropologists have found historical remains on an island in the Atlantic Ocean. The most inspiring thing is that they excavated in a magnificent cave and found that it was a huge tomb. Inside the construction,researchers identified a large number of skeletons, and funeral objects including stone axe, livestock bones and murals. Now, all items have been sorted, and they can be divided into N types. After they were checked attentively, you are told that there are A

i items of the i-th type. Further more, each item of the i-th type requires Bi million dollars for transportation, analysis, and preservation averagely. As your job, you need to calculate the total expenditure.

Input The first line of input contains an integer T which is the number of test cases. For each test case, the first line contains an integer N which is the number of types. In the next N lines, the i-th line contains two numbers A

i and Bi as described above. All numbers are positive integers and less than 101.
Output For each case, output one integer, the total expenditure in million dollars.

Sample Input 1 2 1 2 3 4
Sample Output 14
Source 程式碼如下：

#include <bits/stdc++.h>
using namespace std;

int t,n,a,b;

int main(){
    scanf("%d",&t);
    while(t --){
        int sum = 0;
        scanf("%d",&n);
        for(int i = 0; i < n; i ++){
            scanf("%d%d",&a,&b);
            sum += a*b;
        }
        printf("%d\n",sum);
    }    
    return 0;
}
 

C：hdu5984

Pocky

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 815    Accepted Submission(s): 458


Problem Description Let’s talking about something of eating a pocky. Here is a Decorer Pocky, with colorful decorative stripes in the coating, of length L.
While the length of remaining pocky is longer than d, we perform the following procedure. We break the pocky at any point on it in an equal possibility and this will divide the remaining pocky into two parts. Take the left part and eat it. When it is not longer than d, we do not repeat this procedure.
Now we want to know the expected number of times we should repeat the procedure above. Round it to 6 decimal places behind the decimal point.

Input The first line of input contains an integer N which is the number of test cases. Each of the N lines contains two float-numbers L and d respectively with at most 5 decimal places behind the decimal point where 1 ≤ d, L ≤ 150.

Output For each test case, output the expected number of times rounded to 6 decimal places behind the decimal point in a line.
Sample Input 6 1.0 1.0 2.0 1.0 4.0 1.0 8.0 1.0 16.0 1.0 7.00 3.00
Sample Output 0.000000 1.693147 2.386294 3.079442 3.772589 1.847298
Source

#include <cstdio>
#include <cmath>
#include <cstring>
#include <algorithm>
using namespace std;

int n;
double l,d;

int main(){
	scanf("%d",&n);
	while(n --){
		scanf("%lf%lf",&l,&d);
		if(l <= d) printf("0.000000\n");
		else printf("%.6lf\n",log(l/d) + 1);
	}
	return 0;
}