int test_ex_1_1_18(int argc, const char * argv[]) {
int a = 2, b = 25, m = 3, n = 11;;
printf("%d\n", mystery(a, b));
printf("%d\n", mystery(m, n));
printf("%d\n", mystery2(a, b));
printf("%d\n", mystery2(m, n));
return 0;
}
/*
a的指数增加方式（偶数时增加一倍，奇数时增加一倍，再加1），类似于b的递减（偶数时减少一半，奇数时减1后，再减少一半），所以最终mystery2(a, b) = a ^ b
*/
int mystery2(int a, int b) {
if (b == 0) {
return 1;
}
if (b % 2 == 0) {
return mystery2(a * a, b / 2);
}
return mystery2(a * a, b / 2) * a;
}
int main( void )
{
char string[ SIZE ];
puts( "Enter a string: " );
scanf("%79s", string);
printf("%d\n", mystery2( string ) );
}
int main( void )
{
char string[ 80 ]; /* create char array */
printf( "Enter a string: ");
scanf( "%s", string );
printf( "%d\n", mystery2( string ) );
return 0; /* indicates successful termination */
} /* end main */
int
main(int argc, char *argv[])
{
int x = 4, y = 2;
printf("x = %d, y = %d\n\n",x,y);
mystery2(&x,&y);
printf("x = %d, y = %d\n\n",x,y);
return EXIT_SUCCESS;
}
