贴代码：
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define LEN 100

int main()
{
	char morse[4*LEN+1];
	int lens[LEN+1];
	char out[LEN+1];
	int suites;
	int i, j, k;
	char c;

	char MORSE_TABLE[][30] = {
		".-", "-...", "-.-.", "-..", ".",
		"..-.", "--.", "....", "..", ".---",
		"-.-", ".-..", "--", "-.", "---",
		".--.", "--.-", ".-.", "...", "-",
		"..-", "...-", ".--", "-..-", "-.--",
		"--..", "..--", ".-.-", "---.", "----"
	};

	scanf("%d", &suites);
	c = getchar();

	for(i=0; i<suites; i++)
	{
		memset(morse, 0, 4*LEN+1);
		memset(out, 0, LEN+1);

		j = 0;
		while((c = getchar()) != '\n') {
			if(c == '_') { // underscore
				strcat(morse, MORSE_TABLE[26]);
				lens[j++] = strlen(MORSE_TABLE[26]);
			} else if (c == ',') { // comma
				strcat(morse, MORSE_TABLE[27]);
				lens[j++] = strlen(MORSE_TABLE[27]);
			} else if (c == '.') { // period
				strcat(morse, MORSE_TABLE[28]);
				lens[j++] = strlen(MORSE_TABLE[28]);
			} else if (c == '?') { // question mark
				strcat(morse, MORSE_TABLE[29]);
				lens[j++] = strlen(MORSE_TABLE[29]);
			} else { // character A-Z
				strcat(morse, MORSE_TABLE[c-'A']);
				lens[j++] = strlen(MORSE_TABLE[c-'A']);
			}
		}

		char code[4];
		char *p = morse;
		for(k = j-1; k >= 0; k--) {
			memset(code, 0, 4);
			strncpy(code, p, lens[k]);
			p += lens[k];
			int t;
			for(t = 0; t < 30; t++) {
				if( !strcmp(MORSE_TABLE[t], code) ) {
					if(t == 26)
						out[j-k-1] = '_';
					else if(t == 27)
						out[j-k-1] = ',';
					else if(t == 28)
						out[j-k-1] = '.';
					else if(t == 29)
						out[j-k-1] = '?';
					else
						out[j-k-1] = t + 'A';
				}
			}
		}
		out[j] = '\0';
		printf("%d: %s\n", i+1, out);
	}

	return 0;
}

给一些新的测试用例也可以～～先谢过～～