C中 #号输出错误（未知原因

[Error] invalid conversion from 'char' to 'const char*' [-fpermissive]

#include <stdio.h>


main() {
	int  c, lg[12], i, l;
	for (c = 0; c < 12; ++c)
		lg[c] = 0;
	l = 0;
	while ((i = getchar()) != EOF)
		if (i >= 'a' && i <= 'z' || i <= 'Z' && i >= 'A')
			l++;
		else ++lg[l - 1];

	for (c = 0; c < 12; ++c) {

		printf("%d", c + 1);
		i = lg[c];
		while (i-- != 0)
			printf("#");//原因是这里之前用的单引号？？？
		putchar('\n');
	}



}