#include <stdio.h>
void h( int* sum, int* grade, int n ) {
int i;
for( i=0; i<n; i++ )
sum[ grade[i] / 10 ]++;
}
int main( int argc, char** argv ) {
int grade[12] = { 100, 95, 47, 88, 86, 92, 75, 89, 81, 70, 55, 80 };
int sum[11] = {0};
int i;

h( sum, grade, 12 );
for( i=0; i<10; i++ )
printf( "%d-%d:%d\n", i*10,i*10+9,sum[i] );
printf( "100:%d\n", sum[10] );
}