gistfile1.c

PolyPointer readp()
{/*read in the polynomial */
  	PolyPointer node = NULL, c, headnode;
  	float coef=1;
  	int expon, i=0, count=0;
	char str[100], tempc;

	
	scanf("%s", str);
	while (str[i] != '\0' ){
		int sign = (int)coef;
		expon = 0;
		count = 1;

		//printf("*c[%d]=%c* ",i,str[i]);
		c = GetNode();
		if(str[i] < '9' && str[i] > '0'){
			sscanf(&str[i], "%f", &coef);
			coef *= sign;
			
			c->coef =  coef;
			c->expon = expon;
			c->link = NULL;
			
			for(int k = 10; k <= coef; k*=10) count++;
			i += count;
		}
		switch(str[i]){
			case 'x':
				expon = 1;
				if(str[++i] == '^'){
					sscanf(&str[++i], "%d", &expon);
					for(int k = 10; k <= expon; k*=10) count++;
					i += (count-1);
				}else{
					i--;
				}
				c->expon = expon;
				c->link = NULL;
			break;
			case '+':
				coef = 1;
				i++;
				continue;
			break;
			case '-':
				coef = -1;
				i++;
				continue;
			break;
				
		}
		if(!node){
			headnode = c;
			node = c;
		}else{
			node->link = c;
			node = c;
		}

		if(str[i]!='\0') i++;
	}
	return headnode;
}