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/*************************************************
This program reads in numbers in the range 0 to 100
and prints out a histogram of the numbers, with
"bins" for the ranges [0,10), [10-20), ... ,[90,100].
 *************************************************/
#include <stdio.h>

//-- PROTOTYPES -----------------------------//
int bin(double x);
void rep(char c, int k);

//-- MAIN -----------------------------------//
int main() {
  // Create and initialize histogram
  int H[10] = {0};

  // Read values and update histogram counts
  printf("Enter data entries, followed by -1.\n");
  double value;
  scanf(" %lg", &value);
  while (value >= 0) {
    ++ H[ bin(value) ];
    scanf(" %lg", &value);
  }

  // Print out histogram in ASCII
  for(int k=0; k < 10; ++k) {
    printf("%i:", k);
    rep('*', H[k]);
    printf("\n");
  }

  return 0;
}

//-- FUNCTION DEFINITIONS -------------------//
// Categorizes value x into bins 0, 1, 2, ..., 9
int bin(double x) {
  int i = x/10;
  if (i > 9) {
    return 9;
  } else if (i < 0) {
    return 0;
  } else {
    return i;
  }
}

void rep(char c, int k) {
  for(int i = 0; i < k; i++) {
    printf("%c", c);
  }
}