TheAlgorithms-C/misc/catalan.c

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/*
code for computing nth catalan number
*/
#include <stdio.h>
long int factorial(int x) // long int for more than 10 factorial
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{
int i;
long int fac; // fac stores x factorial
fac = x;
for (i = 1; i < x; i++) // loop to calculate x factorial
{
fac = fac * (x - i);
}
return fac; // returning x factorial
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}
int main()
{
long int f1, f2, f3; // long int for more than 10 factorial
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int n;
float C; // C is catalan number for n;
scanf("%d", &n);
f1 = factorial(2 * n);
f2 = factorial(n + 1);
f3 = factorial(n);
C = f1 / (f2 * f3); // formula for catalan number for n
printf("%0.2f", C);
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return 0;
}