求最大公约数

#include <stdio.h>int gcd( int x, int y ); /* function prototype */int main(){    int j; /* loop counter */   int a; /* first number */   int b; /* second number */   /* loop for 5 pairs of inputs */   for ( j = 1; j <= 5; j++ ) {       printf( "Enter two integers: " );      scanf( "%d%d", &a, &b );      /* find greatest common divisor of a and b */      printf( "The greatest common divisor "         "of %d and %d is %d\n\n", a, b, gcd( a, b ) );   } /* end for */   return 0; /* indicate successful termination */} /* end main *//* gcd find greatest common divisor of x and y */int gcd( int x, int y ){    int i;   int greatest = 1; /* current gcd, 1 is minimum */   /* loop from 2 to smaller of x and y */   for ( i = 2; i <= ( ( x < y ) ? x : y ); i++ ) {      /* if current i divides both x and y */      if ( x % i == 0 && y % i == 0 ) {         greatest = i; /* update greatest common divisor */      } /* end if */   } /* end for */   return greatest; /* return greatest common divisor found */} /* end function gcd */