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  1.     #include <stdio.h>
  2.     #include <stdlib.h>
  3.     #include <sys/types.h>
  4.     #include <omp.h>
  5.     #include <unistd.h>
  6.     #include <time.h>
  7.     #include <math.h>
  8.     #define N 100000
  9.  
  10.     void pi1()
  11.     {
  12.         long double pi = (double)4/3;
  13.         long double tmp2;
  14.         long long int i = 2;
  15.         long int limit = N;
  16.         for(i=2; i<limit; ++i)
  17.         {
  18.             tmp2 = (double)(4*i*i)/(4*i*i-1);
  19.             pi = pi * tmp2;
  20.         }
  21.         printf("liczba pi (mnozenie)  = %.30Lf\n", 2.0*pi);
  22.     }
  23.  
  24.     void pi2()
  25.     {
  26.         long double pi = 0;
  27.         long double tmp1;
  28.         long int i = 0;
  29.         long int limit = N;
  30.         for(i = 0; i<limit; ++i)
  31.         {
  32.             if(i % 2 == 0)
  33.             {
  34.                 tmp1 = (double)(1)/(2*i+1);
  35.             }
  36.             else
  37.             {
  38.                 tmp1 = (double)(-1)/(2*i+1);
  39.             }
  40.             pi = pi + tmp1;
  41.         }
  42.         printf("liczba pi (dodawanie) = %.30Lf\n", 4.0*pi);
  43.     }
  44.  
  45.     void pi3()
  46.     {
  47.         long double pi_mnoz = (double)4/3;
  48.         long double pi_dod = 0;
  49.         long double tmp1, tmp2;
  50.         long long int i = 0;
  51.         long int limit = N;
  52.         for(i = 0; i<limit; ++i)
  53.         {
  54.             if(i % 2 == 0)
  55.             {
  56.                 tmp1 = (double)(1)/(2*i+1);
  57.             }
  58.             else
  59.             {
  60.                 tmp1 = (double)(-1)/(2*i+1);
  61.             }
  62.  
  63.         	if (i >= 2)
  64.             {
  65.             	 tmp2 = (double)(4*i*i)/(4*i*i-1);
  66.                  pi_mnoz = pi_mnoz * tmp2;
  67.         	}
  68.  
  69.             pi_dod = pi_dod + tmp1;
  70.         }
  71.         printf("\nwersja polaczona:\n");
  72.         printf("liczba pi (dodawanie) = %.30Lf\n", 4.0*pi_dod);
  73.         printf("liczba pi (mnozenie)  = %.30Lf\n", 2.0*pi_mnoz);
  74.     }
  75.  
  76.  
  77.     int main()
  78.     {
  79.         clock_t t1 = time(NULL), t2, t3;
  80.         //omp_set_num_threads(8);
  81.         printf("\nN = %d\n", N);
  82.  
  83.         printf("\noddzielnie:\n");
  84.         pi1();
  85.         pi2();
  86.         t2 = time(NULL);
  87.         printf("=> Liczone oddzielnie: %f\n", difftime(t2, t1));
  88.  
  89.         pi3();
  90.         t3 = time(NULL);
  91.         printf("=> Liczone razem: %f.\n",difftime(t3, t2));
  92.  
  93.         return 0;
  94.     }
Success #stdin #stdout 0.01s 2248KB
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N = 100000

oddzielnie:
liczba pi (mnozenie)  = 3.141584799578706571707847894359
liczba pi (dodawanie) = 3.141582653589793491756207433063
=> Liczone oddzielnie: 0.000000

wersja polaczona:
liczba pi (dodawanie) = 3.141582653589793491756207433063
liczba pi (mnozenie)  = 3.141584799578706571707847894359
=> Liczone razem: 0.000000.


	

		
	 
	
	
			

					
			
			
			
			
			
			
			
			

			
			
			
		

	
		
		

			

			                        







			
			

				

	
					
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language:

						
C (gcc 8.3)

					

					

						
created:
								
						
10 years ago

					

					

						
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