posted in OJ题解 

GPA

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1421 Accepted Submission(s): 598
 
Problem Description
Each course grade is one of the following five letters: A, B, C, D, and F. (Note that there is no grade E.) The grade A indicates superior achievement , whereas F stands for failure. In order to calculate the GPA, the letter grades A, B, C, D, and F are assigned the following grade points, respectively: 4, 3, 2, 1, and 0.
Input
The input file will contain data for one or more test cases, one test case per line. On each line there will be one or more upper case letters, separated by blank spaces.
Output
Each line of input will result in exactly one line of output. If all upper case letters on a particular line of input came from the set {A, B, C, D, F} then the output will consist of the GPA, displayed with a precision of two decimal places. Otherwise, the message "Unknown letter grade in input" will be printed.
Sample Input
A B C D F
B F F C C A
D C E F
Sample Output
2.00
1.83
Unknown letter grade in input
Author
2006Rocky Mountain Warmup
Source
HDU “Valentines Day” Open Programming Contest 2009-02-14
Recommend
lcy
 
 
 
 
代码:
 

#include <iostream>
using namespace std;

int main()
{
 char st[100];
 int n, i;
 double sum, flag;

 while (gets(st))
 {
  flag = 1;
  n = strlen(st);
  sum = 0;
  for (i = 0; i < n; i++)
  {
   if (st[i] == ' ')
    sum += 0;
   else if (st[i] == 'A')
    sum += 4;
   else if (st[i] == 'B')
    sum += 3;
   else if (st[i] == 'C')
    sum += 2;
   else if (st[i] == 'D')
    sum += 1;
   else if (st[i] == 'F')
    sum += 0;
   else
   {
    cout << "Unknown letter grade in input" << endl;
    flag = 0;
    break;
   }
  }
  if (flag)
  {
   cout.setf(ios::fixed);
   cout.precision(2);
      cout << sum / ((n + 1) / 2) << endl;
  }
 }

 return 0;
}

 
经验总结:
     1.一组花括号内,break放到最后。
     2.一些有可能会用的模块,用flag来标记,决定是否调用

本文章迁移自http://blog.csdn.net/timberwolf_2012/article/details/7646378

posted in OJ题解 

decimal system

Time Limit: 3000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1546 Accepted Submission(s): 619

Problem Description

As we know , we always use the decimal system in our common life, even using the computer. If we want to calculate the value that 3 plus 9, we just import 3 and 9.after calculation of computer, we will get the result of 12.
But after learning <>,we know that the computer will do the calculation as the following steps:
1 computer change the 3 into binary formality like 11;
2 computer change the 9 into binary formality like 1001;
3 computer plus the two number and get the result 1100;
4 computer change the result into decimal formality like 12;
5 computer export the result;

In the computer system there are other formalities to deal with the number such as hexadecimal. Now I will give several number with a kind of change method, for example, if I give you 1011(2), it means 1011 is a number in the binary system, and 123(10) means 123 if a number in the decimal system. Now I will give you some numbers with any kind of system, you guys should tell me the sum of the number in the decimal system.

Input

There will be several cases. The first line of each case contains one integers N, and N means there will be N numbers to import, then there will be N numbers at the next N lines, each line contains a number with such form : X1….Xn.(Y), and 0<=Xi<Y, 1<Y<=10. I promise you that the sum will not exceed the 100000000, and there will be at most 100 cases and the 0<N<=1000.

Output

There is only one line output case for each input case, which is the sum of all the number. The sum must be expressed using the decimal system.

Sample Input

3
1(2)
2(3)
3(4)

4
11(10)
11(2)
11(3)
11(4)

Sample Output

6
23

Source

HDU 2007-6 Programming Contest

Recommend

xhd

代码:

#include
#include
using namespace std;

int main()
{
int n, a, b;
char c, d;

while (cin >> n)
{
int sum = 0;
while (n--)
{
cin >> a >> c >> b >> d;
int k = 0;
while (a)
{
sum += a % 10 * pow(b, k++);
a /= 10;
}
}
cout << sum << endl;
}

return 0;
}

 

 

PS:

 

C语言中的数学函数:pow  

       原型:在TC2.0中原型为extern float pow(float x, float y); ,而在VC6.0中原型为double pow( double x, double y );

  头文件: math.h

  功能:计算x的y次幂。

  返回值:x应大于零,返回幂指数的结果。

本文章迁移自http://blog.csdn.net/timberwolf_2012/article/details/7630013

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