41 lines
863 B
C
41 lines
863 B
C
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#include <stdio.h>
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#include <string.h>
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#define STRING "test string with lost of stuff"
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int strindex(char source[], char searchfor[]);
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/* pass optional searchfor arg to strindex with STRING, pretty print result */
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int main(int argc, char *argv[])
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{
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char s[] = STRING;
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char *t = (argc > 1) ? argv[1] : "est";
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int i = strindex(s, t);
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if (i < 0) {
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printf("no match\n");
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return 1;
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}
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printf("%s\n", s);
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while (i--)
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putchar(' ');
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printf("^\n");
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return 0;
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}
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/* strindex: return index of the righmost occurence of t in s, -1 if none */
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int strindex(char s[], char t[])
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{
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int i, j;
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const int tlen = strlen(t);
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j = tlen - 1;
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for (i = strlen(s)-1; i; i--)
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if (s[i] != t[j])
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j = tlen - 1;
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else if (!(j--)) // match found
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return i;
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return -1;
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}
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