系统级编程：Solution_week07.doc

1. Are there any memory errors in the following programs? If so, list all of them. Assume that the user enters in correct input, and that the sizes entered are at least one. Write your solution in a text or Word file and submit it below. void main() char *str, *input;int *ilist;int i, size1, size2;printf(Number of letters in word: );scanf(%d, &size1); /* user inputs an integer */printf(Number of integers: );scanf(%d, &size2); /* user inputs an integer */str = (char *) malloc(size1);ilist = (int *) malloc(size2);改为：str = (char *) malloc(size1*sizeof(char)+1);ilist = (int *) malloc(size2*sizeof(int);printf(Word: );scanf(%s, str); /* user inputs a string */for(i = 0; i size2; i+) printf(Number %d of %d: , i + 1, size2);scanf(%d, ilist + i); /* user inputs an integer */free(str);free(ilist);str = nullilist = null;2. Are there any memory errors in the following program? If so, list all of them. Write your solution in a text or Word file and submit it below. /* return 1 if str is 1, 0 otherwise */int checkIf1(char *str) char *newstr = (char *)malloc(strlen(str) + 1);strcpy(newstr, str); /* set newstr to str */if (strcmp(newstr, 1) = 0) /* newstr is 1 */free(newstr);newstr = null;return 1;free(newstr);newstr = null;return 0;void main() char *strArr4 = 1, 2, 3, 4;int i;for(i = 0; i 4; i+) printf(%dn, checkIf1(strArri);3. Are there any memory errors in the following program? If so, list all of them. Write your solution in a text or Word file and submit it below. struct data char *str1, *str2; /* returns two strings concatenated if they are not the same, NULL otherwise */char *mergeSingleIfDifferent(char *s1, char *s2) char *str = (char *) malloc(strlen(s1) + strlen(s2) + 1);if (strcmp(s1, s2) = 0) /* strings are equal */str = NULL;else strcpy(str, s1);strcat(str, s2);return str;/* copies merged strings (or NULL) into array of strings passed in (results) */void mergeArrayIfDifferent(char *results, char *strA1, char *strA2, int size) int i;for(i = 0; i size; i+) resultsi = mergeSingleIfDifferent(strA1i, strA2i); void printAndFree(int c, char *str) if (str != NULL) printf(%d: %sn, c, str);free(str);elsefree(str);void main() char *strArr18 = 1, 2, 3, 4, 5, 6, 7, 8;char *strArr28 = a, 2, c, 4, e, 6, g, 8;char *results8;int i;mergeArrayIfDifferent(results, strArr1, strArr2, 8);for(i = 0; i 8; i+) printAndFree(i, resultsi);void GetMemory(char *p)p = (char *)malloc(100);void Test(void) char *str = NULL;GetMemory(str);strcpy(str, hello world);printf(str);请问运行Test函数会有什么样的结果？答：程序崩溃。因为GetMemory并不能传递动态内存，Test函数中的 str一直都是 NULL。strcpy(str, hello world);将使程序崩溃。char *GetMemory(void)char p = hello world;return p;void Test(void)char *str = NULL;str = GetMemory();printf(str);请问运行Test函数会有什么样的结果？答：可能是乱码。因为GetMemory返回的是指向“栈内存”的指针，该指针的地址不是 NULL，但其原现的内容已经被清除，新内容不可知。void GetMemory2(char *p, int num)*p = (char *)malloc(num);void Test(void)char *str = NULL;GetMemory(&str, 100);strcpy(str, hello);printf(str);请问运行Test函数会有什么样的结果？答：（1）能够输出hello（2）内存泄漏void Test(void)char *str = (char *) malloc(100);strcpy(str,