Pointer exercises in C Language

/*************************************** ******************************** // 01. C * // * compare the size with the pointer pointing to the function *//************************* **************************************** * ******/# include <stdio. h> int min (int A, int B) {If (A> B) return B; elsereturn A;} int main () {int (* p) (INT, INT); // pointer to the function variable P, the parameter must specify the type, otherwise the error P = min; // P points to the min function int A, B, RE; printf ("enter two integers: \ n"); scanf ("% d", & A, & B); Re = (* p) (A, B ); printf ("min = % d \ n", RE); return 0 ;} /*************************************** * ******************************** // 02. C * // * use the function that returns the pointer to find the maximum value *//************************* **************************************** * ******/# include <stdio. h> # define arraysize 10int * findmax (int * P, int N) {int I, * max; max = P; // Max points to the first address of the input array & A [0] for (I = 0; I <n; I ++) if (* (p + I)> * max) max = P + I; return Max;} int main () {int A [arraysize]; int * Re; int I; printf (" Enter % d integers \ n ", arraysize); for (I = 0; I <arraysize; I ++) scanf (" % d ", & A [I]); re = findmax (A, arraysize); printf ("maxnum = % d \ n", * Re); Return 0 ;} /*************************************** ******************************** // 03. C * // * use pointers to store array element values in reverse order *//************************ **************************************** * *******/# include <stdio. h> # define arraysize 10 void invert (int * a, int N) {int * First, * Last, * mid; int temp; First = A; // The first address of the array mid = a + (n-1)/2; // point to the intermediate element last = a + n-1; // The end address of the array (; first <= mid; first ++, last --) {temp = * First; * First = * last; * Last = temp;} int main () {int A [arraysize]; int I; printf ("Enter % d integer \ n", arraysize); for (I = 0; I <arraysize; I ++) {scanf ("% d", & A [I]) ;}invert (A, arraysize); for (I = 0; I <arraysize; I ++) printf ("% d", a [I]); Return 0 ;} /*************************************** *********************************//* 04. C * // * use a pointer to implement string matching *//*************************** **************************************** * *****/# include <stdio. h> # include <string. h> // stra is the string to be matched, and strb is the string to be matched. // find straint match (char * strb, char * stra) in strb) {int I, j, startpos = 0; // int Lena = strlen (stra)-1; int lenb = strlen (strb)-1; int endmatch = Lena; // compare whether the last character of stra is the same as the character in strb. If the character is the same, compare whether stra and strb match for (j = 0; endmatch <= lenb; endmatch + +, Startpos ++) {If (strb [endmatch] = stra [Lena]) for (j = 0, I = startpos; j <Lena & strb [I] = stra [J];) {I ++; j ++;} If (j = Lena) // matched {return (startpos + 1) ;}} if (endmatch> lenb) {printf ("not matchable \ n"); Return-1;} return 0 ;} int main () {char a [] = "abaabcac"; char B [] = "acabaabcaabaabcac"; int P = match (B, A); If (P! =-1) {printf ("matchable \ n"); printf ("the start position is % d \ n", P);} return 0 ;} /*************************************** * ******************************** // * 05. C * // * use a pointer to find the maximum element, and output the subscript of the array where the maximum element is located *//***************************** **************************************** * **/# include <stdio. h> # define arraysize 10int * findmax (int * a, int N, Int & script) {int * max; max = A; int I; for (I = 0; I <n; I ++) {If (* (a + I)> * max) {max = (a + I); script = I ;}} return Max ;} int main () {int * max; int A [arraysize]; int I, SCR; printf ("Enter % d integers:", arraysize); for (I = 0; I <arraysize; I ++) {scanf ("% d", & A [I]);} max = findmax (A, arraysize, Scr ); printf ("Max num is: A [% d] = % d \ n", Scr, * max); return 0 ;} /*************************************** * ******************************** // 06. C * // * Find the same element in two arrays *//************************** **************************************** * *****/# include <stdio. h> # define arraysizea 5 # define arraysizeb 4 // sort the array void sort (int * a, int N) {int I, j; int temp; for (I = 0; I <n-1; I ++) for (j = I + 1; j <n; j ++) {If (* (a + I)> * (a + J) {temp = * (a + I); * (a + I) = * (a + J); * (a + J) = temp ;}}// find the same element int * Find (int * a, int * B, int an, int bn) {int * PTA, * PTB; PTA = A; PTB = B; while (PTA <(a + an) & PTB <(B + bn) {If (* PTA <* PTB) PTA ++; else if (* PTA> * PTB) PTB ++; else // equal return PTA;} return 0 ;}int main () {int I; int * Re; int A [arraysizea], B [arraysizeb]; printf ("Enter % d integers in array A:", arraysizea); for (I = 0; I <arraysizea; I ++) scanf ("% d", & A [I]); printf ("Enter % d integers in array B:", arraysizeb ); for (I = 0; I <arraysizeb; I ++) scanf ("% d", & B [I]); sort (A, arraysizea); sort (B, arraysizeb); Re = find (a, B, arraysizea, arraysizeb); printf ("same num is % d \ n", * Re); Return 0 ;}