Caracteres - pesquisando e removendo ocorrências

Localizar e remover ocorrências de um caractere numa frase previamente digitada pelo usuário
é a finalidade deste código didático.
O programa está funcionando perfeitamente aqui no meu eclipse, e aposto que funcionará
com perfeição na sua IDE favorita, portanto aproveite este ótimo trabalho dedicado a estudantes
de linguagens C.

Veja abaixo imagens do programa em execução:

Veja abaixo o código do programa:

#include <stdio.h>

#include <conio.h>

void Janela5 ( ) {

     int lin, col;

     col = 0;

     system ( "Color 40" );

     for ( lin = 2; lin <= 24; lin++ )

         for ( col = 2; col <= 78; col++ ) {

              gotoxy ( col, lin );

              textbackground ( LIGHTCYAN );

              printf ( " " );

         }

}

int continuando ( ) {

     int nr;

     do {

         system ( "Color 90" );

         Janela5 ( );

         textcolor ( LIGHTRED );

         gotoxy ( 20, 3 );

         printf ( "CARACTERES - PESQUISANDO E REMOVENDO OCORRÊNCIAS " );

         textcolor ( BROWN );

         gotoxy ( 25, 7 );

         printf ( "Programa desenvolvido por:" );

         textcolor ( GREEN );

         gotoxy ( 52, 7 );

         printf ( "Samuel Lima" );

         textcolor ( BLACK );

         gotoxy ( 34, 9 );

         printf ( "sa_sp10@hotmail.com" );

         textcolor ( LIGHTBLUE );

         gotoxy ( 23, 11 );

         printf ( "Digite " );

         textcolor ( LIGHTRED );

         printf ( " 0 " );

         textcolor ( LIGHTBLUE );

         printf ( " para sair ou " );

         textcolor ( LIGHTRED );

         printf ( " 1 " );

         textcolor ( LIGHTBLUE );

         printf ( " para continuar " );

         textcolor ( LIGHTRED );

         gotoxy ( 24, 13 );

         scanf ( "%d", &nr );

         fflush ( stdin );

         if ( nr == 0 ) {

              textcolor ( LIGHTRED );

              gotoxy ( 36, 18 );

              printf ( "MUITO OBRIGADO" );

              getche ( );

              exit ( 0 );

         } else if ( nr == 1 ) {

              return 1;

         }

         textcolor ( BLACK );

         gotoxy ( 36, 16 );

         printf ( "\aopcão errada!" );

         getche ( );

     } while ( 1 );

     return 0;

}

int main ( ) {

     system ( "title CARACTERES - PESQUISANDO E REMOVENDO OCORRÊNCIAS" );

     continuando ( );

     system ( "cls" );

     Janela5 ( );

     unsigned int cont, i, j, lenv;

     char *st_r;

     st_r = ( char* ) malloc ( 10 * sizeof(char) );

     char str [ 255 ];

     textcolor ( LIGHTRED );

     gotoxy ( 20, 3 );

     printf ( "CARACTERES - PESQUISANDO E REMOVENDO OCORRÊNCIAS " );

     textcolor ( LIGHTBLUE );

     gotoxy ( 7, 5 );

     printf ( "Digite uma frase ==> " );

     textcolor ( BLACK );

     gets ( str );

     textcolor ( LIGHTBLUE );

     gotoxy ( 7, 7 );

     printf ( "Frase digitada ==> " );

     textcolor ( BLACK );

     printf ( " %s", str );

     do {

         textcolor ( LIGHTBLUE );

         gotoxy ( 7, 9 );

         printf ( "Digite um caracter  para ser removido ==> " );

         textcolor ( LIGHTRED );

         gets ( st_r );

         lenv = strlen ( st_r );

         cont = 0;

         for ( i = 0; i <= strlen ( str ); i++ )

              for ( j = 0; j <= strlen ( st_r ); j++ )

                   if ( str [ i ] == st_r [ j ] && str [ i ] != 0 )

                        cont++;

         if ( cont == 0 ) {

              textcolor ( LIGHTBLUE );

              gotoxy ( 7, 13 );

              printf ( "Não há Nenhuma ocorrência de " );

              textcolor ( LIGHTRED );

              printf ( "%s", st_r );

              textcolor ( LIGHTBLUE );

              printf ( " na frase digitada" );

              Sleep ( 1800 );

              textcolor ( LIGHTRED );

              gotoxy ( 7, 15 );

              printf ( "Pressione qualquer tecla para tentar outra vez" );

              getche ( );

              gotoxy ( 7, 13 );

              clreol ( );

              gotoxy ( 30, 15 );

              clreol ( );

              gotoxy ( 7, 15 );

              clreol ( );

              gotoxy ( 42, 9 );

              clreol ( );

         }

     } while ( cont == 0 );

     textcolor ( LIGHTBLUE );

     gotoxy ( 7, 11 );

     printf ( "No nome ==> " );

     textcolor ( BLACK );

     printf ( "%s ", str );

     textcolor ( LIGHTBLUE );

     gotoxy ( 7, 13 );

     printf ( "Foram encontrados " );

     textcolor ( LIGHTRED );

     printf ( " %d ", cont );

     textcolor ( LIGHTBLUE );

     printf ( " Caracteres" );

     textcolor ( LIGHTRED );

     printf ( " %s ", st_r );

     textcolor ( LIGHTBLUE );

     gotoxy ( 7, 15 );

     printf ( "Mostrando abaixo o Nome ==> " );

     textcolor ( BLACK );

     printf ( "%s", str );

     textcolor ( LIGHTBLUE );

     gotoxy ( 7, 17 );

     printf ( "Sem seus " );

     textcolor ( LIGHTRED );

     printf ( " %d ", cont );

     textcolor ( LIGHTBLUE );

     printf ( " caracteres " );

     textcolor ( LIGHTRED );

     printf ( " %s ", st_r );

     textcolor ( LIGHTBLUE );

     printf ( " que foram removidos " );

     textcolor ( BLACK );

     gotoxy ( 7, 19 );

     for ( i = 0; i < strlen ( str ); i++ ) {

         for ( j = 0; j < lenv; j++ )

              if ( str [ i ] == st_r [ j ] )

                   break;

         if ( j == lenv ) {

              printf ( " %c", str [ i ] );

         }

     }

     Sleep ( 1000 );

     textcolor ( LIGHTRED );

     gotoxy ( 36, 23 );

     printf ( "MUITO OBRIGADO" );

     getche ( );

     return ( 0 );

}