Mathematics 1201: Programming in C
		 Model Solutions to Homework Assignment #12
			     Prof. Wickerhauser

Exercise 2 of Chapter 12, p.361

 (a),(b),(c):  int x,y,z; scanf("%d %d %d", &x,&y,&z);

 (d) #include <stdio.h>
     main(void) {
       char s[2];			/* string for the names X, Y, Z */
       int x,y,z, v, n;
       for(n=0; n<3; n++) {
	 scanf("%*[ ]%1[XYZ]%*[ =]%d", s,&v);	/* read, e.g., `Z= 23' */
	 switch(*s) {				/* was it X, Y, or Z? */
	 case 'X': x = v; break;
	 case 'Y': y = v; break;
	 case 'Z': z = v; break;
	 }
       }
       printf("x=%d, y=%d, z=%d\n", x, y, z);
       exit(0);
     }

Exercise 4 of Chapter 12, p.361

 (a) #include <stdio.h>
     main(void) {
       int total=0;
       while( scanf("%*c") != EOF) ++total;
       printf("total=%d\n", total);
       exit(0);
     }

 (b) #include <stdio.h>
     main(void) {
       int totallines=0;
       while( scanf("%*[^\n]") != EOF) { /* skip to end of the current line */
	 ++totallines;		/* count this line */
	 scanf("%*1[\n]");		/* skip one newline */
       }
       printf("total lines = %d\n", totallines);
       exit(0);
     }

 (c) #include <stdio.h>
     main(void) {
       int chars = 0, lines=0, Ch;
       while( scanf("%*[^\n]%n", &Ch) != EOF) {
	 chars += Ch;		/* count these characters */
	 scanf("%*1[\n]");		/* skip one newline */
	 ++lines;			/* count this line */
	 ++chars;			/* count the newline character */
       }
       printf("total lines = %d; total characters = %d\n", lines, chars);
       exit(0);
     }

Exercise 5 of Chapter 12, p.361
	"r" : a,c	"w" : b,d	"a" : e
	"r+": a,c,d	"w+": b,c,d	"a+": c,e

Exercise 8 of Chapter 12, p.361
	On my system, fclose(stdin) sets the end-of-file flag on stdin,
	so subsequent scanf() calls return without assigning anything.