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Task/Rep-string/C/rep-string.c

@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <string.h>
+
+int repstr(char *str)
+{
+    if (!str) return 0;
+
+    size_t sl = strlen(str) / 2;
+    while (sl > 0) {
+        if (strstr(str, str + sl) == str)
+            return sl;
+        --sl;
+    }
+
+    return 0;
+}
+
+int main(void)
+{
+    char *strs[] = { "1001110011", "1110111011", "0010010010", "1111111111",
+        "0100101101", "0100100", "101", "11", "00", "1" };
+
+    size_t strslen = sizeof(strs) / sizeof(strs[0]);
+    size_t i;
+    for (i = 0; i < strslen; ++i) {
+        int n = repstr(strs[i]);
+        if (n)
+            printf("\"%s\" = rep-string \"%.*s\"\n", strs[i], n, strs[i]);
+        else
+            printf("\"%s\" = not a rep-string\n", strs[i]);
+    }
+
+    return 0;
+}