C语言2007年试题

PARTⅠ: GIVE A DECISION. circle …T‟for true and …F‟ for false(10marks, 1 mark per point)1. The value of the expression 8==8==8 is 1. T F2. An array name is the address of the first element of the array. T F3. typedef merely adds a new name for some existing type. T F4. Evaluate !(1 &&0 ||!1) as true or false T F5. The null character …\0‟ terminates all character strings. T F6. The output of the following is *successful----- *main() {pri ntf(“*%15.10s*”,” successfully”);}T F7. Assuming enum week { MON, TUE=2, WES, THUR, FRI, SAT, SUN};the value of SAT is 6 . T F8. In C, the value of the expression 9/8 is 0 T F9. For an array declaration a[][2]={0,1,2,3,4,5,6,7,8}; the row size is 4. T F10. automatic and register variables have undefined initial values. T FPARTⅡ: SINGLE CHOICE QUESTIONS（40marks, 2marks per question）1. The C program consists of ______________.A)a main function and some subroutines B)functionsC)procedures D)subroutines.2. Which of the following constant is invalid?______________A) 0818 B) 2.5e-2 C) 2f D) 0xA53. What does strcat (an_array, “this”); do?_______________A) finds “this” in an_arrayB) adds “this” to the end of an_arrayC) compares an_array and “this”D) copies “this” into an _array4. Which operator has the highest precedence?____________A．+= B．++ C．? : D．[ ]5. Which of the following operator can be used as an unary-operator? ___________A．+= B．% C．* D．/6. Which one is wrong if it is used as a character constant? _____________A．”1” B．‟1‟ C．1 D．‟\n‟7. According to the declaration: int a[10], *p=&a[2]; the last element of the array a is ______.A ．a[10]B ．p[9]C ．p[8]D ．p[7]8. Assuming that the value of grade is …C‟, predict what gets printed _________. switch(grade ){ case ‘A ’:printf(“*”);case ‘B ’:printf(“**”);case ‘C ’:printf(“***”);case ‘D ’:printf(“****”);default :printf(“#”);}A) *** B) **** C) ***# D) *******#9. .For the variable names below, which group is the one whose all variable names are invalid ?__________A ）PrintfB ）sort_1row string_to_floatIF EnumC) register D) DOUBLE1P book_pricet.abc A2B10 As we know that a library function double acos(double x) )1,1(-∈x which is included in “math.h”. which one of the following works properly?___________A #include “stdio.h” int y=acos(2);B #inlcude “math .h” int z; z=acos(0.5);C #include “math.h” double y,x; y=acos (x);D #include “math.h” int x,z; z=acos(x=0.3);11. Assuming that the user of a program is asked to enter a day number (1-7) into an integervariable called day . Which of the following while loops is valid?____________A. while (day >= 1 || day <= 7){printf("ERROR 1 - 7 only, enter again: ");scanf(“%d”, &day); }B. while (day >= 1 && day <= 7){printf("ERROR 1 - 7 only, enter again: ");scanf(“%d”, &day); }C. while (day < 1 || day > 7){printf("ERROR 1 - 7 only, enter again: ");scanf(“%d”, &day); }D. while (day <= 1 || day >= 7){printf("ERROR 1 - 7 only, enter again: ");scanf(“%d”, &day); }12. Which one is wrong? ___________A ．char str[10]; str="string";B ．char str[ ]="string";C ．char *p="string";D ．char *p; p="string";13. According to the declaration: int p[5], *a[5]; Which of the following expression iscorrect?______________A．p=a B．p[0]=a C．*(a+1)=p D．a[0]=214. Predict what gets printed: __ .void swap(int *a, int *b){ int *k;k=a; a=b; b=k;}main(){ int a=3, b=6, *x=&a, *y=&b;swap(x,y);printf("%d %d", a, b);}A) 6 3 B) 3 6 C) compiling error D) 0 015. Predict what gets printed: _________________# include <stdio. h>int a=10, b, x, y;void num (){ int a=15,b=10;x = a - b; y = a + b;printf("%d, %d\n”, x, y):}main (){ a= 7,b =5; num (); }A) not for sure B) 12,2 C) 5,25 D) 0,2016. Assuming #define sum(a, b) a + b predict the value of: 5 * sum(3 + 1, 2) ____________.A. 30B. 18C. 22D. none of the above17. What is the main problem with the following: __________int *ip;for (*ip = 0; *ip < 5; *ip++);A) Nothing is wrong.B) It dereferences(间接引用) an uninitialized pointer.C) It does nothing useful.D) It contains implementation dependent problem(s).18. Predict the output from: __________if (5 < 4)if (6 > 5)putchar('1');else if (4 > 3)putchar('2');elseputchar('3');putchar('4');A) 4B) 2C) 24D) 4 or 24, depending upon the implementation.19.What is the main problem with the following?______________①main( )②{ int a[10],i;③for (i=0;i<10;i++)④scanf (“%d”,a[i]);⑤for (i=0;i<10;i++)⑥a[i]= a[i+1];⑦}A) Nothing is wrong.B) Line④is wrong.C) Line⑥is wrong.D) Both line④and ⑥are wrong.20. The program segment (程序段) below reverses(逆序) the string s in the place, which one is written correctly?_______________A）for (i = 0, j = strlen(s); i < j; i++, j--)c = s[i], s[i] = s[j], s[j] = c;B) for (i = 0, j = strlen(s)-1; i < j; i++, j--)c = s[i], s[i] = s[j], s[j] = c;C）for (i = 0, j = strlen(s)-1; i < j; i++, j--)c = s[i]; s[i] = s[j]; s[j] = c;D) for (i = 0, j = strlen(s); i < j; i++, j--)c = s[i]; s[i] = s[j]; s[j] = c;PAR TⅢ: FILL IN THE BLANKS (20marks, 1 mark per blank)1. Write a conditional expression to calculate the maximum of x and y.___________.2. Predict the value of the expression ~ (10^2) &7 ___________.3. Predict what gets printed______________.char *st[ ]={"ONE","TWO","THREE","FOUR"};printf("%s, %c\n", *(st+2), **st+1);4. Predict what gets printed._____________int f (int x){if(x<=1) return 1;else return f(x-1)+f(x-2);}void main ( ){ printf("%d", f(4));}5. After running the program below , if the output (z)is 9.00，please predict the initial value of x. main(){ int a=7, b=2;float x= __________ , y=1.1,z;z=a/2+b*x/y+1/2;printf("%.2f\n", z );}6. Here is a declaration:union {unsigned long l_num;unsigned char c_num[4];} d;Assuming that d.l_num=0x36c3a1f, what is the value of d.c_num[2]?__________.How many bytes does the variable d hold in the memory? __________7. Predict what gets printed: __ .main(){ int x;for (x=1; x<10; x++){ if (x<3) continue;x*=2 ;printf(“#”);}}9. Predict what gets printed: _ ..void fun(){ static int a=1;a*=a+1; printf(“%d,”,a);}main(){ int cc;for(cc=1;cc<4;cc++) fun();}10. Predict what gets printed:______________.main(){ int array [] = {2, 8, 3, 11, 13, 2, 8, 2};int k;int total = 0;for ( k = 0; k < 8; k++ ) {if ( array [k] % 2) break;total += array [k];}printf ( “%d ”, total );}11. Assuming int a[3][3]={2,4,6,8,10,12,14,16}; the value of *(a[2]+2) is ___________.12. Here is a binary search function that decides if a particular value occurs in the sorted array v.int binsearch(int x, int v[], int n) /* binsearch: find x in v[0] <= v[1] <= ... <= v[n-1] */ { int low, high, mid;low = 0; high = n - 1;while (low<high) {mid = (low+high)/2;if (____________) high = mid -1 ;else if (____________) low = mid+1;else /* found match */return mid;}return -1; /* no match */}13. Function itoa: convert an integer n to characters in s , fill in the blanksvoid itoa(int n, char s[]){ int i, sign;if ((sign = n) < 0) /* record sign */n = -n; /* make n positive */i = 0;do { /* generate digits in reverse order */s[i++] = _______________; /* get next digit */} while ((__________) > 0); /* delete it */if (sign < 0)s[i++] = '-';s[i] = '\0';reverse(s);}14. Write the prototype(原型) for the following C functionFunction name : maxReturn data type: intInput data types: two input values of type int________________________15. Predict what gets printed:_________________.void melon (int g, int * h);int main (void){ int a = 1, b = 2;melon ( a, &b );printf ( "a = %d, b = %d", a, b );}void melon (int b, int * c){ b++;*c = *c + b;}16. Here is a function month_day which converts the day of the year into the day of month. void month_day(int year, int yearday, int *pmonth, int *pday){ static int day_tab[2][13]={{0,31,28,31,30,31,30,31,31,30,31,30,31},{0,31,29,31,30,31,30,31,31,30,31,30,31}};int k, leap;leap = year % 4==0 && year % 100 != 0 || year % 400 == 0;for(k=1; yearday > day_tab[leap][k]; k++)____________________；*pmonth = _____________ ；*pday = yearday;}17. The program below calculates the value of s = 1/1! + 1/2! + 1/3! + ……+ 1/n!. Assuming that the input is positive(n>0), fill in the blanks to complete the program.#include <stdio.h>void main( ){ int j, k, n;float f, s;scanf("%d", &n);s=0;for (k=1 ; k<=n; k++){f=1 ;for(j=1; j<=k; j++)____________ ;s=s+1.0/f;}printf("sum=%f\n", s);}。