c - 如何仅使用指针在 C 中重新调用字符串数组

Question

char * players[3]={"Player 1","Player 2","Player 3";
char *p = *players;
char *temp;
for(int t = 0; t < 2; t++)
     {
         temp = *(p+t);
         *(p+t) = *(p+t+1);
         *(p+t+1) = temp;
     }

如何仅使用指针来重新调用数组？我不希望它是这样的:“玩家 2”、“玩家 3”、“玩家 1”

Answer 1

看起来您想要进行左移(旋转)。
这是一个非常简单的操作

• 将指针指向头部
• 对于每个元素，使该点指向下一个元素
• 把头放在尾部上

代码:

#include <stdio.h>

void rotateLeft( char **arr, int elements )
{
    // keep a pointer to the head
    char *head = arr[0];

    // shift every element left
    for (int i=0; i<(elements-1); i++)
    {
        arr[i] = arr[i+1];
    }

    // put the head on the tail
    arr[elements-1] = head;
}

// EDIT - rotate without [] notation.
void rotateLeftNoArrayNotation( char **arr, int elements )
{
    // keep a pointer to the head
    char *head = *arr; //arr[0];

    // shift every element left
    for (int i=0; i<(elements-1); i++)
    {
        *(arr+i) = *(arr+i+1); //arr[i] = arr[i+1];
    }

    // put the head on the tail
    *(arr+elements-1) = head; //arr[elements-1] = head;
}

int main( void )
{
    char *players[3] = { "Player 1", "Player 2", "Player 3" };

    for (int i=0; i<3; i++)
        printf( "players[%u] = \"%s\"\n", i, players[i] );

    rotateLeftNoArrayNotation( players, 3 );

    for (int i=0; i<3; i++)
        printf( "players[%u] = \"%s\"\n", i, players[i] );

    return 0;
}

这给出:

$ ./rotLeft
players[0] = "Player 1"
players[1] = "Player 2"
players[2] = "Player 3"
players[0] = "Player 2"
players[1] = "Player 3"
players[2] = "Player 1"