47655
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写了个求质数的程序
首先输入求质数的范围（0-n)然后回车，附带显示进度。。。。。
算法好像很烂，就是用i除一个比i小，比1大的数,看是否能除尽。。。。。
#include "stdio.h"
#include "conio.h"
void nop(void){
}
void main(void)
{
char f[30];
int b=0;
unsigned long int a;
scanf("%d",&a);
unsigned long int i;
unsigned long int c=0;
unsigned long int o=0;
//float k,l=0.0;
FILE *fp;
fp=fopen("zhishu.txt","wt");
for(i=1;i<a;i++){
for(c=2;c<i;c++){
if(i%c==0){
goto n;
}
}
sprintf(f,"%d\n",i);
fputs(f,fp);
n:
if(i - o==5000){
o=i;
printf("%d/%d\n",i,a);
}
}
fclose(fp);
}
算法好像很烂，就是用i除一个比i小，比1大的数,看是否能除尽。。。。。
#include "stdio.h"
#include "conio.h"
void nop(void){
}
void main(void)
{
char f[30];
int b=0;
unsigned long int a;
scanf("%d",&a);
unsigned long int i;
unsigned long int c=0;
unsigned long int o=0;
//float k,l=0.0;
FILE *fp;
fp=fopen("zhishu.txt","wt");
for(i=1;i<a;i++){
for(c=2;c<i;c++){
if(i%c==0){
goto n;
}
}
sprintf(f,"%d\n",i);
fputs(f,fp);
n:
if(i - o==5000){
o=i;
printf("%d/%d\n",i,a);
}
}
fclose(fp);
}
