Write a modified strcmp function which ignores cases and returns -1 if s1 < s2, 0 if s1 = s2, else returns 1.
1) Iterate through every character of both strings and do following for each character.
…a) If str1[i] is same as str2[i], then continue.
…b) If inverting the 6th least significant bit of str1[i] makes it same as str2[i], then continue. For example, if str1[i] is 65, then inverting the 6th bit will make it 97. And if str1[i] is 97, then inverting the 6th bit will make it 65.
…c) If any of the above two conditions is not true, then break.
2) Compare the last (or first mismatching in case of not same) characters.
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1) Iterate through every character of both strings and do following for each character.
…a) If str1[i] is same as str2[i], then continue.
…b) If inverting the 6th least significant bit of str1[i] makes it same as str2[i], then continue. For example, if str1[i] is 65, then inverting the 6th bit will make it 97. And if str1[i] is 97, then inverting the 6th bit will make it 65.
…c) If any of the above two conditions is not true, then break.
2) Compare the last (or first mismatching in case of not same) characters.
int ic_strcmp(char *s1, char *s2){ int i; for (i = 0; s1[i] && s2[i]; ++i) { /* If characters are same or inverting the 6th bit makes them same */ if (s1[i] == s2[i] || (s1[i] ^ 32) == s2[i]) continue; else break; } /* Compare the last (or first mismatching in case of not same) characters */ if (s1[i] == s2[i]) return 0; if ((s1[i]|32) < (s2[i]|32)) //Set the 6th bit in both, then compare return -1; return 1;}