add lec3

section01/Lec03/src/eighth.c

+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+
+	float pi = 3.1415926;
+	char *pf = (char*) &pi;
+	int i;
+
+	printf("pi= %f\n\n", pi);
+
+	for (i=0; i<4; i++) {
+		printf("pf[%d]= %02x\n", i, 0xff & pf[i]);
+	}
+}

section01/Lec03/src/eighth.c~

+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+
+	float pi = 3.1415926;
+	char *pf = (char*) &pi;
+	int i;
+
+	printf("pi= %f\n\n", pi);
+
+	for (i=0; i<4; i++) {
+		printf("pf[%d]= %02hhx\n", i, pf[i]);
+	}
+}

section01/Lec03/src/list.c~

+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void){
+    struct employee_node{
+        char name[10];
+        int id;
+        float wage;
+        struct employee_node *next;
+    };
+
+    struct employee_node *first;
+
+    first = malloc(struct employee_node);
+
+    
+    
+}

section01/Lec03/src/scanf.c

+#include <stdio.h>
+
+int main(void){
+    int   i;
+    float x;
+    char text[80];
+
+    scanf("%d", &i);
+    scanf("%f", &x);
+    scanf("%s", text);
+    printf(" i= %d\n", i);
+    printf(" x= %f\n", x);
+    printf(" text= %s\n", text);
+}

section01/Lec03/src/seventh.c

+#include <stdio.h>
+#include <string.h>
+
+int main(int argc, char* argv[]) {
+
+	int i;
+
+	char p[] = "This is a test.";
+
+	for (i=0; i<strlen(p); i++) {
+		printf("%c", p[i]);
+	}
+	printf("\n\n");
+
+	printf("string starting at p= %s\n", p); 
+	printf("content of p= %p\n\n", p);
+
+	char *s = p;
+	printf("string starting at s= %s\n", s);
+	printf("length= %d\n", (int) strlen(s));
+	printf("s[5]= %c\n", s[5]);
+	printf("*(s+6)= %c\n\n", *(s+6));
+}

section01/Lec03/src/struct.c

+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void){
+    struct employee_node{
+        char name[10];
+        int id;
+        float wage;
+        struct employee_node *next;
+    };
+
+    struct employee_node *first;
+    
+    printf ("allocating %lu Bytes\n", sizeof(*first));
+    first = malloc(sizeof(*first));
+    printf ("memory is at %p\n", first);
+    
+    
+}

section01/Lec03/src/struct.c~

+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void){
+    struct employee_node{
+        char name[10];
+        int id;
+        float wage;
+        struct employee_node *next;
+    };
+
+    struct employee_node *first;
+    
+    printf ("allocating %lu Bytes\n", sizeof(first));
+    first = malloc(sizeof(first));
+    printf ("memory is at %p\n", first);
+    
+    
+}

section01/Lec03/src/third.c

+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+	{
+		int i = 999;
+		int j = 666;
+		printf("i= %d, j= %d\n", i, j);
+		{
+			int i = 123;
+			int j = i*i;
+			printf("i= %d, j= %d\n", i, j);
+		}
+		printf("i= %d, j= %d\n", i, j);
+	}
+}

section01/Lec03/src/thirdA.c

+#include <stdio.h>
+
+int i = 7;
+float x = 2.71828;
+double y = 3.1415926;
+char c = 'w';
+
+int main(int argc, char* argv[]) {
+	printf("%d, %c, %f, %lf\n", i, c, x, y);
+    printf("i@%p\n", &i);
+}

section01/Lec03/src/thirdA.c~

+#include <stdio.h>
+
+int i = 7;
+float x = 2.71828;
+double y = 3.1415926;
+char c = 'w';
+
+int main(int argc, char* argv[]) {
+	printf("%d, %c, %f, %lf\n", i, c, x, y);
+}

section01/Lec03/src/thirdB.c

+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+	int i = 7;
+	float x = 2.71828;
+	double y = 3.1415926;
+	char c = 'w';
+
+	printf("%d, %c, %f, %lf\n", i, c, x, y);
+    printf("i@%p\n", &i);
+}

section01/Lec03/src/thirdB.c~

+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+	int i = 7;
+	float x = 2.71828;
+	double y = 3.1415926;
+	char c = 'w';
+
+	printf("%d, %c, %f, %lf\n", i, c, x, y);
+}

section01/Lec03/src/thirdC.c

+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+	static int i = 7;
+	float x = 2.71828;
+	static double y = 3.1415926;
+	char c = 'w';
+	printf("%d, %c, %f, %lf\n", i, c, x, y);
+}