Kernighan and Richie's Vertical Word Histogram Example

histovert.c

#include <stdio.h>

#define IN      1   /* we're inside a word  */
#define OUT     0   /* we're outside a word */
#define SPACE   8   /* we're outside a word */

#define PSPREV  0
#define PSNULL  1 

int main(){
  int i, c, w, f, pstate, wsize, state, maxdepth;
  int sizes[10];

  pstate = PSNULL;
  state = OUT;
  wsize=1;
  maxdepth=0;

  /* loop over array and initialize to zero */
  for (i = 0; i < 10; ++i)
    sizes[i] = 0;

  while ((c = getchar()) != EOF) {

    /* if ws, nl, or tab STAY OUT! */
    if(state == IN && (c == ' ' || c == '\n' || c == '\t')){
      state = OUT;
      ++sizes[wsize];
      if (sizes[wsize] > maxdepth){
        maxdepth = sizes[wsize];
      }
      wsize=1;
    }else if (state == IN){
    /* if we're in keep counting the letters */
      ++wsize;
    }else if (state == OUT)
    /* if none of those things but we're OUT 
     * Move to in and start counting letters
     */
      state = IN;
  }

  /* Print Results */

  /* Print bars from top down */
  for(i=maxdepth; i > 0; i--){
    putchar('\n');
    for(w=0; w < 10; w++){
      if(w>0)
        if(pstate == PSNULL)
            for(f=0; f < SPACE; f++)
                putchar(' ');
        if(pstate == PSPREV)
            for(f=0; f < SPACE - 1; f++)
                putchar(' ');
      if (sizes[w] == i){
        putchar('_');
        pstate = PSPREV;
        --sizes[w];
      }else
        pstate = PSNULL;
    }
  }

  /* Print bottom axis */
  putchar('\n');
  for(i=0; i < 10; i++){
    printf("--------"); 
  }
  putchar('\n');
  for(i=0; i < 10; i++){
    printf("%d\t", i); 
  }
  putchar('\n');
  for(i=0; i < 10; i++){
    printf("--------"); 
  }
  putchar('\n');
}

two two two two two some things are not what they would seem                                                                                                  
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