1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <err.h> 4 5 int 6 main(void) 7 { 8 char line[1024]; 9 size_t i = 0; 10 while (fgets(line, sizeof(line), stdin) != NULL) { 11 if ((size_t)atoi(line) != i) 12 errx(EXIT_FAILURE, "bad line %s\n", line); 13 i++; 14 } 15 return EXIT_SUCCESS; 16 } 17