完成了level1中的作业

level1/p01_runningLetter/runningLetter.c

@@ -0,0 +1,43 @@
+#include <stdio.h>
+#include <windows.h>
+
+#define WINDOW_WIDTH 76
+
+void move(int dir)
+{
+	int i,j;
+	for(i=1;i<=WINDOW_WIDTH;i++)
+	{
+		Sleep(1);
+		system("cls");
+		if(dir==1)
+		{
+			for(j=1;j<=i;j++)
+			{
+				printf(" ");
+			} 
+			printf("test");
+		}
+		if(dir==-1)
+		{
+			for(j=WINDOW_WIDTH-i;j>=1;j--)
+			{
+				printf(" ");
+			} 
+			printf("test");
+		}
+
+	}
+}
+int main()
+{
+	printf("test"); 
+	for(;;)
+	{
+	  	move(1);
+		move(-1); 
+	}
+	return 0;
+}
+
+

level1/p02_isPrime/isPrime.c

@@ -0,0 +1,31 @@
+#include <stdio.h> 
+
+int n,i;
+int main()
+{
+ 	scanf("%d", &n);
+	if(n==1)
+	{
+		printf("1 is not a prime number nor a composite number.\n");
+		exit(0);
+	}
+	if(n<=0)
+	{
+		printf("Please input a positive integer!");
+		scanf("%d", &n);
+	}
+	for(i=2;i*i<=n;i++)
+	{
+		if(n%i==0) 
+		{
+			printf("%d is not a prime.\n", n);
+			exit(0);
+		}
+	}
+	printf("%d is a prime.\n", n);
+
+ 	return 0;
+}
+
+
+

level1/p03_Diophantus/Diophantus.c

@@ -0,0 +1,17 @@
+#include <stdio.h>
+#include <math.h>
+
+#define eps 1e-9
+
+double x;
+int main()
+{
+	//x=1/6x+1/12x+1/7x+5+1/2x+4
+	for(x=1;x<=200;x++)
+	{
+		if(fabs(x/6+x/12+x/7+5+x/2+4-x)<eps)
+		printf("%d\n",(int)x);
+	}
+
+	return 0;
+}

level1/p04_ narcissus/narcissus.c

@@ -0,0 +1,17 @@
+#include <stdio.h> 
+
+int n,i;
+int main()
+{
+ 	for(i=100;i<=999;i++)
+	{
+		int a=i/100, b=(i/10)%10, c=i%10;
+		if(a*a*a+b*b*b+c*c*c==i)
+		printf("%d\n", i); 
+	}
+
+ 	return 0;
+}
+
+
+

level1/p05_allPrimes/allPrimes.c

@@ -0,0 +1,23 @@
+#include <stdio.h>
+#include <time.h>
+
+#define MAXN 1000
+int prime[MAXN+1],i,j;
+int main()
+{
+	double begin=clock();
+	for(i=2;i<=MAXN;i++)
+	{
+		if(!prime[i]) prime[++prime[0]]=i;
+		for(j=1;j<=prime[0] && prime[j]<=MAXN/i;j++)
+		{
+			prime[prime[j]*i]=1;
+			if(i%prime[j]==0) break;
+		}
+	}
+	for(i=1;i<=prime[0];i++)
+		printf("%d\n", prime[i]);
+	double end=clock();
+	printf("%f\n", (end-begin)/CLOCKS_PER_SEC);
+	return 0;
+}