Question

我想将input.txt文件更改为整数数组。但是可悲的是，每当遇到换行符时，我总是会丢失一个整数。

以下是我的main（）

int main(int args, char* argv[]) {
  int *val;

  char *STRING = readFile();

  val = convert(STRING);

  return 0;
}

以下是我的文件输入功能

char *readFile() {
    int count;
    FILE *fp;

    fp = fopen("input.txt", "r");
    if(fp==NULL) printf("File is NULL!n");

    char* STRING;
    char oneLine[255];
    STRING = (char*)malloc(255);
    assert(STRING!=NULL);

    while(1){
        fgets(oneLine, 255, fp);
        count += strlen(oneLine);
        STRING = (char*)realloc(STRING, count+1);
        strcat(STRING, oneLine);
        if(feof(fp)) break;
    }
    fclose(fp);
    return STRING;
}

以下是我的整数数组函数

int *convert(char *STRING){
    int *intarr;
    intarr = (int*)malloc(sizeof(int)*16);
    int a=0;
    char *ptr = strtok(STRING, " ");


    while (ptr != NULL){
        intarr[a] = atoi(ptr);

        printf("number = %s\tindex = %d\n", ptr, a);
        a++;
        ptr = strtok(NULL, " ");
    }

    return intarr;
}

Answer 1

有很多问题。

这是您程序的更正版本，所有注释均为我的。为简便起见，进行了最小限度的错误检查。如果文件中包含16个以上的数字，<properties> <wagon.url>cifs://dedcdevfs01/Seepub/QS</wagon.url> <wagon.fromDir>manasa-utility/</wagon.fromDir> <wagon.toDir>target/resources/testdata/</wagon.toDir> </properties> <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>wagon-maven-plugin</artifactId> <version>1.0</version> <executions> <execution> <id>downloadFilesInShare</id> <phase>compile</phase> <goals> <goal>download</goal> </goals> <configuration> <serverId>${wagon.serverId}</serverId> <url>${wagon.url}</url> <skip>${wagon.skip}</skip> <fromDir>${wagon.fromDir}</fromDir> <toDir>${wagon.toDir}</toDir> </configuration> </execution> </executions> <inherited>false</inherited> </plugin>将是一个问题，应该以某种方式处理它，例如，通过将intarr = malloc(sizeof(int) * 16);与intarr一起增长，类似于您在进行的操作realloc。

readFile

我不确定您的要求是什么，但这可以简化很多，因为不需要将文件读入内存，然后将字符串转换为数字。您可以在阅读数字时即时转换数字。并且正如注释中已经提到的那样，为每一行调用#include <stdio.h> #include <string.h> #include <stdlib.h> #include <assert.h> char *readFile() { FILE *fp; fp = fopen("input.txt", "r"); if (fp == NULL) { printf("File is NULL!n"); return NULL; // abort if file could not be opened } #define MAXLINELENGTH 255 // define a constant rather than hardcoding "255" at several places char* STRING; char oneLine[MAXLINELENGTH]; STRING = malloc(MAXLINELENGTH); int count = MAXLINELENGTH; // count mus be initialized and better declare it here assert(STRING != NULL); STRING[0] = 0; // memory pointed by STRING must be initialized while (fgets(oneLine, MAXLINELENGTH, fp) != NULL) // correct usage of fgets { count += strlen(oneLine); STRING = realloc(STRING, count + 1); strcat(STRING, oneLine); } fclose(fp); return STRING; } int *convert(char *STRING, int *nbofvalues) { // nbofvalues for returning the number of values int *intarr; intarr = malloc(sizeof(int) * 16); int a = 0; char *ptr = strtok(STRING, " \n"); // strings may be separated by '\n', or ' ' *nbofvalues = 0; while (ptr != NULL) { intarr[a] = atoi(ptr); printf("number = %s\tindex = %d\n", ptr, a); a++; ptr = strtok(NULL, " \n"); // strings are separated by '\n' or ' ' } // read the fgets documentation which // terminates read strings by \n *nbofvalues = a; // return number of values return intarr; } int main(int args, char* argv[]) { int *val; char *STRING = readFile(); if (STRING == NULL) { printf("readFile() problem\n"); // abort if file could not be read return 1; } int nbvalues; val = convert(STRING, &nbvalues); // nbvalues contains the number of values // print numbers for (int i = 0; i < nbvalues; i++) { printf("%d: %d\n", i, val[i]); } free(val); // free memory free(STRING); // free memory return 0; }效率很低。还有更多改进的空间。

C编程：将文本文件的行转换为整数数组

1 个答案: