#include <stdio.h>
#include <string.h>
 
void trimmer(char frase[]) {
 
	//Parametros iniciais
	int posPrimeiroChar=0;
	int posUltimoChar=strlen(frase)-1;
	int i;
 
	//Encontra primeiro caractere diferente de espaço
	while (frase[posPrimeiroChar] == ' ') posPrimeiroChar++;
	while (frase[posUltimoChar] == ' ') posUltimoChar--;
 
	//Rearranja string
	for (i = posPrimeiroChar; i <= posUltimoChar; i++) {
		frase[i-posPrimeiroChar] = frase[i];
	}
 
	//Finaliza a string
	frase[i-posPrimeiroChar] = '\0';
}
 
int main(){
 char frase[]="    Eu nao fui a escola!    ";
 printf("%s %lu\n",frase,strlen(frase));
 trimmer(frase);
 printf("%s %lu\n",frase,strlen(frase));
 return 0;
}

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