#include <stdio.h>

char grade( int exam1, int exam2, float exam_weight );

main()
{
     int ans, mid_term, final;
     float weight;
     char letter_grade;

     do {
          printf( "\n\nCompute another grade (1 = Yes, 0 = No)? " );
          scanf( "%d", &ans );
          if ( ans == 1 ) {
               printf( "\nEnter mid term, final, weight: " );
               scanf( "%d%d%f", &mid_term, &final, &weight );
               letter_grade = grade( mid_term, final, weight );
               printf( "Grade is: %c\n", letter_grade );
          }
     } while ( ans == 1 );
}

char grade( int exam1, int exam2, float exam1_weight )
{
     float average;

     average = exam1_weight * exam1 + ( 1.0 - exam1_weight ) * exam2;
     if ( average > 7.0 )
          return 'P';
     else
          return 'F';
}