C Language--three methods to find the length of a string

Problem:

Three methods for finding a string

I. Method of counting

#include <stdio.h> #include <assert.h>int my_strlen (char* str) {int Count=0;while (*STR) {count++;str++;} return count;} int main (void) {char *arr = "ABCEF"; int ret = My_strlen (arr);p rintf ("%d\n", ret);}

Second, the pointer-pointer method

#include <stdio.h> #include <assert.h>int my_strlen (const CHAR*STR) {assert (SRT); const CHAR* RET = Str;while (*ret++) {;} return (RET-STR-1);} int main (void) {char *arr = "abcdef"; printf ("%d\n", My_strlen (arr));}

Third, the method of recursion

#include <stdio.h> #include <assert.h>int my_strlen (char* srt) {assert (SRT), if (*srt = = ') {return 0;} else{Srt++;return (1 + my_strlen (SRT));}} int main (void) {char *arr = "abcdef";p rintf ("%d\n", My_strlen (arr));}

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C Language--three methods to find the length of a string