title: It should print true if the second argument is fully contained within the first argument, but it prints false
body: <pre><code>#include &lt;stdio.h&gt;
  #include &lt;string.h&gt;
  
  int main(int argc, char **argv){
    char *str1, *str2;
    int str1len, str2len; 
    str1 = argv[1]; str2 = argv[2];
    str1len=strlen(str1);
    str2len=strlen(str2);
  
    if (str2len&gt;str1len){
      printf("false\n");
      return 0;
    }
    char sub1[100];
    for (int i=0;i&lt;str1len-str2len;i++){
      strncpy(sub1,str1+i,str2len);
      if (strcmp(sub1,str2)==0){
        printf("true\n");
      }
      printf("false\n");
      return 0;
    }
  }
  </code></pre>
  
  <p>I don't know what part of it is wrong that it doesn't work.
  This is the question: a program that takes two text strings as arguments and prints "true" followed by a newline if the second string is entirely contained within the first, or "false" followed by a newline otherwise.</p>