实验四

#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 = %f, x2 = %f\n", x1, x2);
}
else {
real = -b/(2*a);
imag = sqrt(-delta) / (2*a);
printf("x1 = %f + %fi, x2 = %f - %fi\n", real, imag, real,imag);
}
}
}

#include <stdio.h>

long long fac(int n);

int main() {
int i,n;
printf("Enter n: ");
scanf("%d", &n);
for(i=1; i<=n; ++i)
printf("%d! = %lld\n", i, fac(i));
return 0;
}

long long fac(int n) {
static long long p = 1;
p = p*n;

return p;
}

#include<stdio.h>
int func(int,int);

int main(){
int k=4,m=1,p1,p2;

p1=func(k,m);
p2=func(k,m);
printf("%d,%d\n",p1,p2);

return 0;
}
int func(int a,int b){
static int m=0,i=2;

i+=m+1;
m=i+a+b;

return (m);
}

理论分析和实验结果一致

 

 

 

#include <stdio.h>

#define N 1000
int fun(int n,int m,int bb[N]){
int i,j,k=0,flag;

for(j=n;j<=m;j++){
flag=1;
for(i=2;i<j;i++)
if(j%i==0){
flag=0;
break;
}
if(flag==1)
bb[k++]=j;
}
return k;
}
int main(){
int n=0,m=0,i,k,bb[N];

scanf("%d",&n);
scanf("%d",&m);

for(i=0;i<m-n;i++)
bb[i]=0;

k=fun(n,m,bb);
for(i=0;i<k;i++)
printf("%4d",bb[i]);

return 0;
}

 

#include <stdio.h>
long long fun(int n);

int main() {
int n;
long long f;

while(scanf("%d", &n) != EOF) {
f = fun(n);
printf("n = %d, f = %lld\n", n, f);
}
return 0;
}

long long fun(int n){
if (n==0)
return 0;
else
return fun(n-1)*2+1;
}

#include<stdio.h>
void draw(int n,char symbol);
#include<stdio.h>
int main(){
int n,symbol;
while(scanf("%d %c",&n,&symbol)!=EOF){
draw(n,symbol);
printf("\n");
}
return 0;
}
void draw(int n,char symbol){

int line,i,m;
for(line=1;line<=n;line++){
for(i=1;i<=n-line;i++){

printf(" ");
}
for(m=1;m<=2*line-1;m++){

printf("%c",symbol);
}
printf("\n");
}
}