created lec2

section01/Lec02/src/fourth.c

+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+
+	int i, j;
+
+	j=0;
+	for (i=0; i<100; i++) {
+		j += i;
+	}
+	printf("i= %d, j= %d\n\n", i, j);
+
+	i=0; j=0;
+	while (i<100) {
+		j += i;
+		i++;
+	}
+	printf("i= %d, j= %d\n\n", i, j);
+
+	i=0; j=0;
+	do {
+		j += i;
+		i++;
+	} while (i<100);
+	printf("i= %d, j= %d\n\n", i, j);
+}

section01/Lec02/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/Lec02/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/Lec02/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/Lec02/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);
+}