实验三

Posted 2020-11-22 cfcyt

Part1:

一元二次方程求解

#include <math.h>
#include <stdio.h>
#include <stdlib.h>
int main() {
float a, b, c, x1, x2;
float delta, real, imag;
printf("Enter a, b, c: ");
while(scanf("%f%f%f", &a, &b, &c)) {
if(a == 0)
printf("not quadratic equation. ");
else {
delta = b*b - 4*a*c;
if(delta >= 0) {
x1 = (-b + sqrt(delta)) / (2*a);
x2 = (-b - sqrt(delta)) / (2*a);
printf("x1 = %f, x2 = %f ", x1, x2);
}
else {
real = -b/(2*a);
imag = sqrt(-delta) / (2*a);
printf("x1 = %f + %fi, x2 = %f - %fi ", real, imag, real, imag);
}
}
printf("Enter a, b, c: ");
}
system("pause");
return 0;

}

 

 

 

猜数游戏

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main() {
int guessNumber;
int ans; // 存放用户猜的数字
srand((time(0))); // 以时间函数作为随机种子
guessNumber = 1 + rand()%100; // 生成1~100之间的随机数
do {
printf("your guess number is(1~100): ");
scanf("%d", &ans);
if(ans < guessNumber)
printf("%d is lower than the number. ", ans);
else if(ans > guessNumber)
printf("%d higher then the number. ", ans);
}while(ans != guessNumber);
printf("Congratulations. you hit it~ ");
system("pause"); // 在devc中运行时，这一行可以去掉
return 0;
}

 

 

 

 

Part2

输出最大最小数

#include <stdio.h>
#include <stdlib.h>
int main() {
int number, max, min, n;
n=1;
printf("输入第%d个数: ", n);
scanf("%d", &number);
max = number;
min = number;
while(n<5) {
n++;
printf("输入第%d个数: ", n);
scanf("%d", &number);
if(number>max)
max = number;
else if(number<min)
min = number;
}
printf("最大数为: %d ", max);
printf("最小数为: %d ", min);
system("pause");
return 0;
}

 

 

 

 

Part3

编程输出101-200之间所有素数，并输出这一区间内素数个数。

#include<stdio.h>
#include<math.h>
int main(){
int m,i,k,h=0,leap=1;
printf(" ");
for(m=101;m<=200;m++){
k=sqrt(m+1);
for(i=2;i<=k;i++){
if(m%i==0){
leap=0;
break;
}
}
if(leap){
printf("%-4d",m);
h++;
if(h%10==0){
printf(" ");

}
}
leap=1;

}
printf(" The total is %d",h);



}

 

 

 

将一个长整型数s的每一数位上的奇数依次取出来，构成一个新的数，起高位仍在高位，低位仍在低位.

#include<stdio.h>
int main()
{
unsigned long s,t=0,p=1;
scanf("%u",&s);
while(s!=0)
{
if((s%10)%2!=0)
{
t=t+(s%10)*p;
p=p*10;
}
s=s/10;
}
printf("%u ",t);
return 0;
}

 

 

 

 实验总结：

1.符号在中英文格式下不同，导致程序运行错误

2.不等式顺序不同，导致程序运行错误

number>max 对 

number在前 字母n在后