C语言：函数

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <time.h>
#define PI 3.1415
int main()
{    
    float x=30;
    srand((unsigned)time(NULL));
    printf("%lf\n",tan(x*PI/180));
    printf("%lf\n",log(x*PI/180));
    printf("%lf\n",log10(x*PI/180));
    printf("sin=%lf\n",sin(x*PI/180));
    printf("%lf\n",exp(x*PI/180));
    printf("%lf\n",cos(x*PI/180));
    printf("%lf\n",sqrt(16));//sqrt=Square Root Calculations(平方根函数)
    int a=0,b;
    for (a=0;a<=60;a++)
    {
        b=rand();
        printf("%d,%d,%d\n",b,b%10,b%51+13);//产生0-9之间的随机整数 13-63之间随机整数 
        
        }
        
    getchar();
}