(common enough issue). @B. Nadolson recommends to avoid rolling your own strcicmp() and this is reasonable, except when code needs high equivalent portable functionality. Note how even if the way of writing the conditions in code changes, the outputs remain unchanged in the above programs (as Scaler and Scaled strings are indeed unequal). Let us see the code to get better idea. I got it three examples, its clear now :), Compare two strings character by character in C, Building a safer community: Announcing our new Code of Conduct, Balancing a PhD program with a startup career (Ep. In C because, in most contexts, an array "decays into a pointer to its first element". Your approach with nested loops isn't very well thought-out. Again, potential different results for sorting if code did tolower(toupper(*a)) vs. toupper(tolower(*a)). Do #ifdef _WINDOWS #define strcasecmp stricmp #endif and put it in an appropriate header. @user3605367 Why not, if you provide an empty string? Note the usage of the term lexicographically here, which essentially means in dictionary order. Comparing two strings or string comparison in C involves finding out if they are the same or not. As C lib does not provide such a function, a pre-coded function from some alternate library is recommended. As others have stated, there is no portable function that works on all systems. So all you're doing is comparing pointers. int main(){ char first[1000], second[1000]: int result; printf("Input a string\n"); gets(first); printf("Input a string\n"); gets(second); result = compare_string(first, second); if (result == 0) printf("The strings are same.\n"); else printf("The strings are different.\n"); return 0;}, int compare_string(char *first, char *second) { while (*first == *second) { if (*first == '\0' || *second == '\0') break; first++; second++; }, if (*first == '\0' && *second == '\0') return 0; else return -1;}. There is no function that does this in the C standard. Difference between and . strcmp can be used to compare two strings. Copyrighted Protected. Comments Off on C Program To Compare Two Strings 3 Easy Ways | C Programs. Not the answer you're looking for? How to pass a 2D array as a parameter in C? Otherwise print both the strings are not equal. You might have observed that we used the == relational operator many times above. Connect and share knowledge within a single location that is structured and easy to search. But before we even dive into applying our brain cells in deducing whether strings are equal or not, focus on the string lengths. Duplication or Copying Our Site Content Is Strictly Prohibited. Starting address of both namet2 and nameIt2 are different. UPDATE: what I meant by 'no C string' is, there is no string in C. What's usually referred to as a 'C string' is language independent (as 'Pascal string' is), it's the representation of strings as a null-terminated linear array of characters. Case 2: when the strings are unequal, it returns the difference between ascii values of the characters that differ. How to ignore text case while comparing two strings in C++? The strcmp () function is used to compare two strings two strings str1 and str2. My wording was a little harsh, sorry. This is why you have to use library functions like strcmp() to compare string values. C program to compare two strings In this specific article, we will describe the various ways to compare two different strings in C programming. How can an accidental cat scratch break skin but not damage clothes? Case insensitive comparison of constant strings, C++/CX - Case insensitive comparison of two String objects, compare strings after converting to lower case in c. Is there a way to compare to string pointers ignoring their case? That together with the loop itself and you're traversing a strlen(a)+2 times. The C++ has string class. I want to compare the first letter of the first string with the first letter of the second string, This function is non-standard; Microsoft calls it, @entropo: apologies, POSIX does seem to define, Yes it seems there is such header strings.h and in theory, Note that there's no reason to implement your own, @GustavoVargas Me too, then I decided to write it here and save time for the future myself and others :), Voting down this solution - it advertizes to be a drop-in/tested solution, but a simple additional test using, Hi @GaspardP, thanks for pointing out this edge case. Below is an approach that even performed faster than some system provided functions. The optimal way could be to go digit by digit, from left to right. 4)If c is equal to i then this function returns 1 otherwise it returns 0. 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