CPP2022-10-函数01（上）

1. double dist( double x1, double y1, double x2, double y2 )
2. {
3. return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
4. }

1. int sign( int x )
2. {
3. if(x>0)
4.     {
5. return 1;
6.     }
7. else if(x==0)
8.     {
9. return 0;
10.     }
11. else
12.     {
13. return -1;
14.     }
15. }

1. double fact( int n )
2. {
3. if(n==1)
4.     {
5. return 1;
6.     }
7. else
8.     {
9. return n*fact(n-1);
10.     }
11. }

1. int IsSquare( int n )
2. {
3. if((long long int)sqrt(n)*(long long int)sqrt(n)==n)
4.     {
5. return 1;
6.     }
7. return 0;
8. }