C 练习(三)

//生成 100~200的随机数
#include <stdio.h>
#include <stdlib.h>
int min;
int find(){
   int i, y, x,max;
   x = rand()%101 + 100;
   max = x; min = x;
   printf("生成的随机数为:\n%d\n",x);
   for(i =0;i<9;i++){
      y = rand()%101 + 100;
      printf("%d\t\n",y);
      if(y>max) max = y;
      if(y<min) min = y;
   } 
   return max;
}
void main(){
    int max = find();
    printf("最大数为%d ,最小数为%d",max,min);
} 




//静态变量求1~5的阶层
#include <stdio.h>
#include <stdlib.h>
int fac(int n){
   static int f = 1;
   f *= n;
   return f;
}
void main(){
    
    int k;
    for(k=1;k<=5;k++){
       printf("%d! = %d\n",k,fac(k));
    }
} 
//判断为该年第几天
#include <stdio.h>
int days(int year,int month,int day){

    int i,count=0,monthArr[] = {31,28,31,30,31,30,31,31,90,31,30,31};
    if( ((year%100)&&!(year%4)) || !(year%400)  )
        monthArr[1] = 29;

    for(i=0;i<month-1;i++){
       count += monthArr[i];
    }
    count += day;
    return count;
}
void main(){
    int year,month,day;
    printf("请依次输入年、月、日\n");
    scanf("%d,%d,%d",&year,&month,&day);
    printf("%d年%d月%d日为该年的第%d天",year,month,day,days(year,month,day));
}