c Language practice 15-- nested conditional operator

#include <stdio.h> 
#include <stdlib.h>
 / * Title: using nested conditional operator to complete this question: academic> = 90 points represented by students A, with between 60-89 minutes B represents, by 60 points or less represents C * / 
int main () { 
System ( " Color 1F " );   // set the display frame for the blue white 
System ( " MODE CON Lines cols = 80 = 30 " );   / / fixed display frame size 
/ * ***************************************** program body parting line (top) ************************************************************ * / 
int NUM; 
 the while ( . 1 ) { 
the printf ( " enter score: " ); 
Scanf ( " % D ", & NUM);
     IF (NUM> = 90 ) 
        the printf ( " other times A \ n- " );
     the else  IF (NUM> = 60 ) 
        the printf ( " other times B \ n- " );
     the else 
        the printf ( " other times C \ n- " ); 
}         
/ * ***************************************** program body parting line (bottom) ************************************************************ * / 
    return  0 ; 
}