运行结果：
C语言代码：
/* c how to program 习题3.27 */
// Fig. 3.10: fig03_10.c
// Analysis of examination results
#include <stdio.h>
// function main begins program execution
int main( void )
{
// initialize variables in definitions
unsigned int passes = 0; // number of passes
unsigned int failures = 0; // number of failures
unsigned int student = 1; // student counter
int result; // one exam result
// process 10 students using counter-controlled loop
while ( student++ <= 10 ) {
// prompt user for input and obtain value from user
printf( "%s", "Enter result ( 1=pass,2=fail ): " );
scanf( "%d", &result );
// if result 1, increment passes
//当输入的数字不是1也不是2时提示错误并要求重新输入
while ( result != 1 && result != 2){
printf("你的输入有误，请从新输入！\n");
printf( "%s", "Enter result ( 1=pass,2=fail ): " );
scanf( "%d", &result );
}
// if result 1, increment passes
if ( result == 1 ) {
passes = passes + 1;
} // end if
else{ // otherwise, increment failures
failures = failures + 1;
}
} // end while
// termination phase; display number of passes and failures
printf( "Passed %u\n", passes );
printf( "Failed %u\n", failures );
// if more than eight students passed, print "Bonus to instructor!"
if ( passes >= 8 ) {
puts( "Bonus to instructor!" );
} // end if
} // end function main
/**************************************************************************
* (C) Copyright 1992-2013 by Deitel & Associates, Inc. and *
* Pearson Education, Inc. All Rights Reserved. *
* *
* DISCLAIMER: The authors and publisher of this book have used their *
* best efforts in preparing the book. These efforts include the *
* development, research, and testing of the theories and programs *
* to determine their effectiveness. The authors and publisher make *
* no warranty of any kind, expressed or implied, with regard to these *
* programs or to the documentation contained in these books. The authors *
* and publisher shall not be liable in any event for incidental or *
* consequential damages in connection with, or arising out of, the *
* furnishing, performance, or use of these programs. *
*************************************************************************/
