分割故障误差(C)

Question

我当前正在编写一个程序，该程序应该从文本文件和输出统计信息中接收有关文本的输入统计信息，例如字母数量，单词的大小以及它们发生的频率以及每个单词发生多少次。但是，每次运行程序时，我都会收到一个细分故障错误。该程序一直运行，直到我达到线字母计数分析。我收到分割故障错误。这是一些示例文本：

1你好，我的名字是鲍勃我住在加拿大

数字表示应该读取多少行。我该怎么办才能纠正我的问题？我是编程的新手，所以我敢肯定这是基本的。

 #include <stdio.h>
 #include <string.h>

#define MAX_LINE_LENGTH 80
#define MAX_WORD_LENGTH 20
#define MAX_LINES 10
void letterAnalysis(char [][MAX_LINE_LENGTH], int lineTotal);
int wordLengthAnalysis(char [][MAX_LINE_LENGTH], int lineTotal, int wordLength);
void wordAnalysis(char [][MAX_LINE_LENGTH], int lineTotal);

int main (void){
    int lineTotal, wordSize;
    char text[lineTotal][MAX_LINE_LENGTH];
    char n[1];
    fgets(n, 10, stdin);
    lineTotal = n[0] - '0';

    for(int i = 0; i < lineTotal; i++){
        fgets(text[i], MAX_WORD_LENGTH, stdin);
    }
    printf("n***Letter count analysis***n");
    letterAnalysis(text, lineTotal);
    printf("n***Word length analysis***n");
    for (int i = 1; i <= MAX_WORD_LENGTH; i++){
        wordSize = wordLengthAnalysis(text, lineTotal, i);
        if (wordSize == 1){
            printf("n%-2dtword of length %d", wordSize, i);
        }
        else{
            printf("n%-2dtwords of length %d", wordSize, i);
        }
    }
    printf("nn***Word analysis***n");
    wordAnalysis(text, lineTotal);
    return 0;
}
void letterAnalysis(char text[][MAX_LINE_LENGTH], int lineTotal){
    int alphabet[26] = {0};
    for (int i = 0; i < lineTotal; i++){
        for(int j = 0; j < MAX_LINE_LENGTH; j++){
            switch(text[i][j]){
                case 'A': case 'a':
                alphabet[0]++;
                break;
                case 'B': case 'b':
                alphabet[1]++;
                break;
                case 'C': case 'c':
                break;
                alphabet[2]++;
                case 'D': case 'd':
                alphabet[3]++;
                break;
                case 'E': case 'e':
                alphabet[4]++;
                break;
                case 'F': case 'f':
                alphabet[5]++;
                break;
                case 'G': case 'g':
                alphabet[6]++;
                break;
                case 'H': case 'h':
                alphabet[7]++;
                break;
                case 'I': case 'i':
                alphabet[8]++;
                break;
                case 'J': case 'j':
                alphabet[9]++;
                break;
                case 'K': case 'k':
                alphabet[10]++;
                break;
                case 'L': case 'l':
                alphabet[11]++;
                break;
                case 'M': case 'm':
                alphabet[12]++;
                break;
                case 'N': case 'n':
                alphabet[13]++;
                break;
                case 'O': case 'o':
                alphabet[14]++;
                break;
                case 'P': case 'p':
                alphabet[15]++;
                break;
                case 'Q': case 'q':
                alphabet[16]++;
                break;
                case 'R': case 'r':
                alphabet[17]++;
                break;
                case 'S': case 's':
                alphabet[18]++;
                break;
                case 'T': case 't':
                alphabet[19]++;
                break;
                case 'U': case 'u':
                alphabet[20]++;
                break;
                case 'V': case 'v':
                alphabet[21]++;
                break;
                case 'W': case 'w':
                alphabet[22]++;
                break;
                case 'X': case 'x':
                alphabet[23]++;
                break;
                case 'Y': case 'y':
                alphabet[24]++;
                break;
                case 'Z': case 'z':
                alphabet[25]++;
                break;
            }       
        }
    }
    for(int i = 0; i <= 25; i++){
        printf("%c: t%dn",'a' + i, alphabet[i]);;
    }
}
int wordLengthAnalysis(char text[][MAX_LINE_LENGTH], int lineTotal, int wordLength){
    int sentenceLength;
    int counter, wordSize = 0;
    for(int i = 0; i < lineTotal; i++){
        sentenceLength = strlen(&text[i][0]);
        for(int j = 0; j < sentenceLength + 2; j++){
            if(text[i][j] == ' '){
                if(counter == wordLength){
                    ++wordSize;
                    counter = 0;
                }
                else{
                counter = 0;
                }
            }
            else{
                counter++;
            }
        }
    }
    return wordSize;
}
void wordAnalysis(char text[][MAX_LINE_LENGTH], int lineTotal){
    char maxWords[800];
    char word[MAX_LINE_LENGTH], word2[MAX_WORD_LENGTH], *ptrText, *ptrTextCounter;
    int counter, textCounter = 0;
    int sentenceLength, wordTracker;
    int lineFlag;
    for(int i = 0; i < lineTotal; i++){
        ptrText = &text[i][0];
        sentenceLength = strlen(ptrText);
        counter = 0;
        for (int j = 0; j < sentenceLength + 1; j++){
            wordTracker = 1;
            if (text[i][j] == ' ' ){
                if (counter != 0){
                    sprintf(word, "%.*s", counter, ptrText);
                    ptrTextCounter = &text[i][j+1];
                    lineFlag = j;
                if(strstr(maxWords, word) == NULL){
                    for (int k = i; k < lineTotal; k++){
                        textCounter = 0;
                        if (lineFlag == j){
                            ptrTextCounter = &text[i][j+1];
                        }
                        else{
                            lineFlag = 0;
                            ptrTextCounter = &text[i][j+1];
                        }
                        for ( ; lineFlag < sentenceLength; lineFlag++){
                            if(text[k][lineFlag] == ' '){
                                if (textCounter != 0){
                                    if(textCounter == counter){
                                        sprintf(word2, "%.*s", textCounter, ptrTextCounter);
                                            if(strcmp(word, word2) == 0){
                                                wordTracker++;
                                            }
                                    }
                                    ptrTextCounter = &text[k][lineFlag];
                                    textCounter = 0;
                                }
                                else{
                                    ptrTextCounter = &text[k][lineFlag+1];
                                }
                            }
                            else{
                                textCounter++;
                            }
                        }
                    }
                    if(wordTracker == 1){
                        printf("n"%.*s"ttappeared %d time", counter, ptrText, wordTracker);
                    }
                    else{
                        printf("n"%.*s"ttappeared %d time", counter, ptrText, wordTracker);
                    }
                }

                strcat(maxWords, word);
                    ptrText = &text[i][j+1];
                    counter = 0;
                }
                else{
                    ptrText = &text[i][j+1];
                }
            }
            else{
                counter++;
            }
        }
    }

}

Answer 1

我收到了几个警告：

main.c:17:14: warning: variable length array used [-Wvla]
    char text[lineTotal][MAX_LINE_LENGTH];
             ^
main.c:17:15: warning: variable 'lineTotal' is uninitialized when used here [-Wuninitialized]
    char text[lineTotal][MAX_LINE_LENGTH];
              ^~~~~~~~~

您尚未初始化lineTotal，但正在使用它。这会导致不确定的行为。

main.c:64:21: warning: code will never be executed [-Wunreachable-code]
                    alphabet[2]++;
                    ^~~~~~~~

您的break;可能放错了位置。

main.c:152:20: warning: variable 'counter' may be uninitialized when used here [-Wconditional-uninitialized]
                if(counter == wordLength){
                   ^~~~~~~

再次，您正在使用潜在的非初始化变量。

也：

char n[1];
fgets(n, 10, stdin);

您的数组有一个元素，但您告诉fgets它可以访问到n[10]。

_{提示（如果还不算明显）：切勿在没有警告的情况下编程C。}