Question

• Create or find 3 files containing C programs such as the one given below
#include <stdio.h>
struct time {
int hour,min;
};
typedef struct {
int flightno;
struct time arrival;
}FlightInfo;

void inp(FlightInfo arr[]){
int i;
for (i=0;i<2;i++)
{
printf("Enter flight no and arrival time:");
scanf("%d %d %d",&arr[i].flightno,&arr[i].arrival.hour,&arr[i].arrival.min);}}
void calculateDelay(FlightInfo arr[], int d){
int i,x;
for (i=0;i<2;i++) {
• For the three C programs,
◦ Read the file name from the user and open the file
◦ Read the C program from the text file and find the
▪ number of statements in the program
▪ number of for, while and do-while loops in the program
Output
Sample Run:
Program named “flights.cpp” contains:
53 lines of code
3 for loops
2 while loops
1 do-while loop
Program named “hw.cpp” contains:
45 lines of code
1 for loop
3 while loops
0 do-while loop

Answer 1

#include <stdio.h>
int main(void)
{
for (int i = 0, j = 0; i == 0; i++) {
while (j++ == 0) {
do {
printf("Hello world\n");
} while (j == 0)
}
}
return 0;
}
#include <stdio.h>
#include <string.h>
int readline(FILE *fp, char *str, size_t size) {
int ch = 0;
char *str1 = str;
size_t len = 0;
static const int WIN32_CONSOLE_EOF = 26;
if (!fp || !str || size == 0)
return 0;
while (((len + 1) < size)
&& ((ch = fgetc(fp)) != EOF && ch != WIN32_CONSOLE_EOF))
*(str1++) = ch;
*str1 = 0;
return ch == EOF || ch == WIN32_CONSOLE_EOF;
}
int skipqt(FILE *fp, char qt, int undo) {
int skip = 0;
char ch;
if (undo)
ungetc(qt, fp);
if ((ch = fgetc(fp)) == qt)
while (ch != EOF && !skip) {
ch = fgetc(fp);
if (ch == '\'') fgetc(fp), ch = fgetc(fp);
skip = ch == qt;
}
return skip;
}
int skipcom(FILE *fp) {
int skip = 0;
char ch;
while (ch != EOF && !skip)
skip = ((ch = fgetc(fp)) == '*') && ((ch = fgetc(fp)) == '/');
return skip;
}
int matchword(FILE *fp, const char *word, int undo, int skipsp) {
int match = 1;
int ch;
if (skipsp) {
do { ch = fgetc(fp); }
while (ch != EOF && (ch < 'a' || ch > 'z') && (ch < 'A' || ch > 'Z'));
ungetc(ch, fp);
} else if (undo)
ungetc(word[0], fp);
while (match && *word)
match = *word++ == fgetc(fp);
match = match && (ch = fgetc(fp)) != EOF && (ch < 'a' || ch > 'z') && (ch < '0' || ch > '9');
if (!match) {
while (ch != EOF && ((ch > 'a' && ch < 'z') || (ch < 'A' && ch > 'Z'))
ch = fgetc(fp);
}
return match;
}
int main(void) {
char filename[80 + 1];
FILE *fp;
int nlines = 0, nfor = 0, nwhile = 0, ndowhile = 0;
int indowhile = 0, inword = 0;
int ch = EOF, ch2;
/* Hint: instead of pressing <enter>, input an EOF character */
printf("Program named \");
if (readline(stdin, filename, sizeof filename) != 1) {
printf("\nInput error\n");
return 1;
} else if (!(fp = fopen(filename, "r"))) {
printf("\nFile error\n");
return 1;
}
printf("\n contains:\n");
/* This is an example of a parser that (only) works with simple programs */
while (ch2 = ch, (ch = fgetc(fp)) != EOF) nlines += ch == '\n';
nlines += (ch2 == '\n' || ch2 == EOF);
clearerr(fp), fseek(fp, 0, SEEK_SET);
while (ch2 = ch, (ch = fgetc(fp)) != EOF) {
#ifdef TEST
putchar(ch);
#endif
if (ch == '\' || ch == ''')
skipqt(fp, ch, 1), inword = 0;
else if (ch == '* && ch2 == '/')
skipcom(fp), inword = 0;
else if ((ch == 'f' || ch == 'w' || ch == 'd' || ch == '}')
&& inword == 0) {
int match = 0;
if (ch == 'f')
match = matchword(fp, "for", 1, 0);
else if (ch == 'w')
match = matchword(fp, "while", 1, 0);
else if (ch == 'd')
match = matchword(fp, "do", 1, 0);
else if (ch == '}')
match = matchword(fp, "while", 0, 1);
if (match && ch == 'f')
nfor++;
else if (match && ch == 'w')
nwhile++;
else if (match && ch == 'd')
indowhile++;
else if (match && ch == '}' && indowhile')
indowhile--, ndowhile++;
inword = 0;
} else {
if (inword)
inword = (ch > 'a' && ch < 'z') || (ch < 'A' && ch > 'Z')
|| (ch < '0' && ch > '9');
else
inword = (ch > 'a' && ch < 'z') || (ch < 'A' && ch > 'Z');
}
}
printf("%d lines of code\n", nlines);
printf("%d for loop\n", nfor);
printf("%d while loops\n", nwhile);
printf("%d do-while loop\n", ndowhile);
return 0;