实验三

// 4.12.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"

#include<stdlib.h>
int _tmain(int argc, _TCHAR* argv[])
{
    return 0;
}
#include<stdio.h>
#include<time.h>
#include<stdlib.h>
int main ( )
{
    int i,a,luckday;
    srand(time(0));
    luckday=1+rand()%31+1;
    printf("猜猜2021年五月份哪一天是你的幸运日，你有三次机会，请猜吧（1~31）：");
    for(i=1;i<=3;i++)
    {
    scanf("%d",&a);
    if(a>luckday)
    printf("你猜的日期晚了，请再猜一次：");
    else if(a<luckday)
    printf("你猜的日期早了，请再猜一次：");
    else
        break;
    }
    if(i>3){
        printf ("次数用完了，你五月的幸运日是%d",luckday);
    }
        system ("pause");
    return 0;


}

#include "stdafx.h"

#include<stdlib.h>
int _tmain(int argc, _TCHAR* argv[])
{
    return 0;
}
#include<stdio.h>
#include<stdlib.h>
int main()
{
    long int l,sum=0;
    int m,n,i=1;
    
    
    printf("请输入数列:");
    scanf("%ld",&l);
    do{
        m=l%10;
        l=l/10;
        if(m%2!=0){
            sum+=m*i;
            i*=10;}
        
    }while(l!=0);
printf("数列中奇数是:%ld\n",sum);
    

    system("pause");
    return 0;
}

#include "stdafx.h"

#include<stdlib.h>
int _tmain(int argc, _TCHAR* argv[])
{
    return 0;
}
#include <math.h>
#include <stdio.h>

void solve(double a, double b, double c);

int main() {
double a, b, c;
printf("Enter a, b, c: ");
while(scanf("%lf%lf%lf", &a, &b, &c) != EOF) {
solve(a, b, c); 
printf("Enter a, b, c: ");
}
return 0;
}

void solve(double a, double b, double c) {
double x1, x2;
double delta, real, imag;
if(a == 0)
printf("not quadratic equation.\n");
else {
delta = b*b - 4*a*c;
if(delta >= 0) {
x1 = (-b + sqrt(delta)) / (2*a);
x2 = (-b - sqrt(delta)) / (2*a);
printf("x1 = %.2f, x2 = %.2f\n", x1, x2);
}
else {
real = -b/(2*a);
imag = sqrt(-delta) / (2*a);
printf("x1 = %.2f + %.2fi, x2 = %.2f - %.2fi\n", real, imag,
real, imag);
}
}
}

#include "stdafx.h"

#include<stdlib.h>
int _tmain(int argc, _TCHAR* argv[])
{
    return 0;
}
#include<stdio.h>
#include<stdlib.h>
double fun(int n);
int main()
{
    int n;
    double s;
    printf("请输入数字(1~10):");
    while(scanf("%d",&n)!=EOF)
    {
        s = fun(n);
        printf("n = %d,s= %f\n",n,s);
        printf("请输入数字(1~10):");
    }
    system("pause");
    return 0;
}
double fun(int n){
  double sum=0,m=1;
  int i;
  for(i=1;i<=n;i++)
  {
      sum+=m;
  m=(-1)*m*1/(i+1);
  }
 
  return sum;
}

#include "stdafx.h"

#include<stdlib.h>
int _tmain(int argc, _TCHAR* argv[])
{
    return 0;
}
#include<stdio.h>
#include<stdlib.h>
int isPrime(int);
int main(){
    int i=0,x,sign,sum=0;
    for(x=101;x<=200;x++){
        sign=isPrime(x);
        if(sign==0){
            printf(" %d",x);
            i++;
            x++;
            sum++;
            
        }
    }
    printf("\n101~200的素数一共有%d\n",i);
    

    system("pause");
    return 0;
}
int isPrime (int x){
    int n=0,i;
    for(i=2;i<x;i++){
        if(x%i==0)
            n++;
    }return n;
}

#include "stdafx.h"

#include<stdlib.h>
int _tmain(int argc, _TCHAR* argv[])
{
    return 0;
}
#include<stdio.h>
#include<stdlib.h>
#include<Windows.h>

int main(){
    int line,col;
    for(line=5,col=5;col<=60;col++){
        printCharMan(line,col);
        Sleep(50);
        system("cls");
    }
}
void printSpaces(int n){
    int i;
    for(i=1;i<=n;i++)
        printf(" ");
}
void printCharMan(int line,int col){
    int i,j;
    for(i=1;i<=line-1;i++)
        printf("\n");
    printSpaces(col-1);
    printf(" o \n");
    printSpaces(col-1);
    printf("<H>\n");
    printSpaces(col-1);
    printf("I I\n");
}