完成了level1

level1/p01_runningLetter/p01_runningLetter.c

@@ -0,0 +1,32 @@
+#include<stdio.h>
+#include <windows.h>
+#define TIME 24
+#define WIDE 80
+#define TheChar 'A'
+
+
+void run()
+{
+	int i,j;
+
+	for (i=0;i<WIDE*2;i++)
+	{
+		if (i<=WIDE)
+			for (j=0;j<i;j++)
+				printf(" ");
+		else
+			for (j=WIDE;j>i-WIDE;j--)
+				printf(" ");
+		printf("%c",TheChar);
+		Sleep(TIME);
+		system("cls");
+	}
+
+}
+
+int main()
+{
+	system("mode con cols=81 lines=50");
+	run();
+	return 0;
+}

level1/p02_isPrime/p02_isPrime.c

@@ -0,0 +1,22 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+
+int main()
+{
+    long long n;
+    scanf("%lld",&n);
+
+    long long i;
+    int flag=1;
+    for (i=2;i<=sqrt(n)+1;i++)
+    {
+        if (n%i == 0) flag=0;
+    }
+    if ( flag )
+        printf("%lld is a prime.",n);
+    else
+        printf("%lld is not a prime.",n);
+
+    return 0;
+}

level1/p03_Diophantus/p03_Diophantus.c

@@ -0,0 +1,25 @@
+#include <stdio.h>
+#include <stdlib.h>
+#define INTERVAL 4
+
+int check(int x)
+{
+    int son_die=x-(x/6+x/12+x/7+5)-INTERVAL;
+
+    if (son_die == x/2)
+    {
+        return 0;
+    }
+    return 1;
+}
+
+int main()
+{
+    int the_age=1;
+    while ( check(the_age) )
+    {
+        the_age++;
+    }
+    printf("The age of diophantus when his son died is %d",the_age-INTERVAL);
+    return 0;
+}

level1/p04_ narcissus/p04_ narcissus.c

@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <stdlib.h>
+#define MIN_N 100
+#define MAX_N 1000
+
+int cube(int x)
+{
+    return(x*x*x);
+}
+
+int check(int number)
+{
+    int bit,decade,hundred;
+    bit=number%10;
+    decade=(number/10)%10;
+    hundred=number/100;
+
+    if (cube(bit)+cube(decade)+cube(hundred) == number)
+    {
+        printf("%d=%d^3+%d^3+%d^3\n",number,hundred,decade,bit);
+        return 1;
+    }
+
+    return 0;
+}
+
+int main()
+{
+    int i,num=0;
+
+    for (i=MIN_N;i<MAX_N;i++)
+    {
+        if ( check(i) )
+            num++;
+    }
+    printf("\nThe total of narcissus number is %d.",num);
+
+    return 0;
+}

level1/p05_allPrimes/p05_allPrimes.c

@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#define MIN_N 2
+#define MAX_N 1000
+
+int main()
+{
+    int time_start,time_end,a[MAX_N+5]={0};
+
+    time_start=clock();
+
+    int i,j,num=0;
+    for (i=MIN_N;i<=MAX_N/2+1;i++)
+    {
+        if ( !a[i] )
+            for (j=2;j<=MAX_N/i;j++)
+                if (i*j<=MAX_N) a[i*j]=1;
+
+    }
+    for (int i=MIN_N;i<=MAX_N;i++)
+        if ( !a[i] )
+        {
+            printf("%d  ",i);
+            num++;
+            if (num%10 == 0) printf("\n");
+        }
+    printf("\n\nThe total number of prime is %d.",num);
+
+    time_end=clock();
+
+    printf("\ntime use:%lf ms",(double)(time_end-time_start));
+    return 0;
+}

level1/p06_Goldbach/p06_Goldbach.c

@@ -0,0 +1,29 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#define MIN_N 1
+#define MAX_N 50
+
+int prime(int x)
+{
+    int i;
+    for (i=MIN_N+1;i<=sqrt(x)+1;i++)
+        if (x%i == 0) return 0;
+    return 1;
+}
+
+int main()
+{
+    int i,j;
+    for (i=MIN_N;i<=MAX_N;i++)
+    {
+        for (j=MIN_N;j<=i*2;j++)
+            if (prime(j) && prime(2*i-j))
+            {
+                printf("%d = %d + %d\n",2*i,j,2*i-j);
+                break;
+            }
+    }
+    printf("All even numbers within 100 accord with Goldbach's conjecture.");
+    return 0;
+}

level1/p07_encrypt_decrypt/p07_encrypt_decrypt.c

@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#define MAXN 1000005
+
+char Original_string[MAXN];
+char After_handling[MAXN];
+
+char encrypt(char c,int pos)
+{
+    return(c+(pos+1)*(pos+2));
+}
+
+char decrypt(char c,int pos)
+{
+    return(c-(pos+1)*(pos+2));
+}
+
+
+
+int main()
+{
+    scanf("%s",Original_string);
+    int len=strlen(Original_string);
+
+    printf("After encrypt:");
+    int i;
+    for (i=0;i<len;i++)
+    {
+        printf("%c",encrypt(Original_string[i],i));
+    }
+
+    printf("\nAfter decrypt:");
+    for (i=0;i<len;i++)
+    {
+        printf("%c",decrypt(Original_string[i],i));
+    }
+    return 0;
+}

level1/p08_hanoi/p08_hanoi.c

@@ -0,0 +1,36 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int tot=0;
+
+void move(char a,char c)
+{
+    tot++;
+    printf("Step %d: move from %c to %c\n",tot,a,c);
+}
+
+void hanoi(char a,char b,char c,int n)
+{
+    if (n == 1)
+    {
+        move(a,c);
+    }
+    else
+    {
+        hanoi(a,c,b,n-1);
+        move(a,c);
+        hanoi(b,a,c,n-1);
+    }
+}
+
+int main()
+{
+    int the_number;
+    printf("Please enter the size of hanoi:");
+    scanf("%d",&the_number);
+    printf("\nThe solution is:\n");
+
+    hanoi('A','B','C',the_number);
+
+    return 0;
+}