簡體   English   中英

C-打印2D字符數組

[英]C - Printing a 2D Char Array

如何在C中打印2D字符數組的元素?

這是我當前的代碼:

int main()
{
  unsigned int size;

  printf("Enter size:\n");
  scanf("%d",&size);

  char word[size][size];

  //Enter the matrix
  for(int k = 0; k < (size); ++k){
    for (int j = 0; j < (size); ++j){
      printf("Enter letter:");
      scanf("%c",&word[k][j]);
    }
  }

  //printf("\n");
  for (int k = 0; k < size; ++k){
    for(int j = 0; j < size; ++j){

      printf("%c",word[k][j]);
    }
    //printf("\n ");
  }
  printf("\n");
}

執行后,它將成對返回元素(使用4x4數組)。示例:

ab
cd
ef
gh
ij
kl
mn
op

而不是我想要的輸出:

abcd
efgh
ijkl
mnop

為什么是這樣?

更改scanf可解決所有問題

scanf(" %c",&word[k][j]);  // notice the space before '%c'

而且您還需要將打印循環更改為此

for (k = 0; k < size; ++k){
    for(j = 0; j < size; ++j){
        printf("%c",word[k][j]);
    }
    printf("\n");
}

我刪除了閱讀內容,看來可以打印了:

int main()
{
    const unsigned int size = 4;
    char word[size][size];

    //Enter the matrix
    for (int k = 0; k < (size); ++k) {
        for (int j = 0; j < (size); ++j) {
            word[k][j] = 'a' + j + (k * size);
        }
    }

    for (int k = 0; k < size; ++k) {
        for (int j = 0; j < size; ++j) {

            printf("%c", word[k][j]);
        }
        printf("\n");
    }
    printf("\n");

    getchar();
    return 0;
}

並輸出:

abcd
efgh
ijkl
mnop

我發現您的來源有兩個問題。

一種是內存分配-實際上不是ansi-c。

如果需要動態內存,則需要在運行時分配它。 考慮使用c ++,因為有一些標准的工具可以更安全地為您提供幫助。

第二個問題是緩沖區中有一個空格字符用作輸入字符。 我想你想澄清一下。

這是帶有其他注釋的來源:

#include <stdio.h>
#include <stdlib.h>

void ansiC()
{
    unsigned int size;

    printf("Enter size:\n");
    scanf("%d", &size);

    //char word[size][size]; <- this is not ansi-c because size is unknown at compile time
    char * word = (char*)malloc(sizeof(char)* size * size);


    //Enter the matrix
    for (int k = 0; k < (size); ++k)
    {
        for (int j = 0; j < (size); ++j)
        {
            printf("Enter letter:");
            scanf("%c ", &word[k * size + j]);
            //since word is just a pointer i changed the way the position is calculated
            //after the character the user presses the enter key
            //this puts a whitespace character on the buffer. 
            //by adding the space after %c you also clear that from the buffer
        }
    }

    //printf("\n");
    for (int k = 0; k < size; ++k)
    {
        for (int j = 0; j < size; ++j)
        {

            printf("%c", word[k * size + j]);
            //since word is just a pointer i changed the way the position is calculated
        }
        //printf("\n ");
    }
    printf("\n");

    free(word); //if you use malloc you need to remember to use free
}

int main()
{
    ansiC();
    return 0;
}

注意: %c%1s做不同的事情(除了為后者添加終止null之外):

  • c取每個字符, 包括空格,制表符,cr和lf
  • %1s跳過了所有空格(空格,制表符,cr,lf等)

因此,在輸入時間,您應該使用:

char c[2]; // provide room for a terminating null...
...
for(int k = 0; k < (size); ++k){
    for (int j = 0; j < (size); ++j){
        printf("Enter letter:");
        scanf("%1s",c);
        word[k][j] = c[0];
    }
}

在打印時:

for (int k = 0; k < size; ++k){
    for(int j = 0; j < size; ++j){
        printf("%c",word[k][j]);
    }
    printf("\n "); // new line after each line
}

請檢查一下。

# include <iostream.h>
# include <conio.h>


void main()
{
clrscr();
char arr[5][3]={"abc","aks","tny","dkn","kbf"};
    for(int a=0;a<5;a++)
    {
        for(int b=0;b<3;b++)
        {
            cout<<" "<<arr[a][b];
        }
        cout<<endl;
    }


 getch();
}

暫無
暫無

聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.

 
粵ICP備18138465號  © 2020-2024 STACKOOM.COM