#include <stdio.h>

int main(void)
{
    char a;
    int b;
    int c;
    int d;
    int e;

    scanf("%c", &a);

    for (b = 5, c = 1; c <= b; c++)
    {
        for (d = 5 - c; d > 0; d--)
            printf(" ");
        for (e = 1; e <= c; e++)
            printf("%c ", a);
        printf("\n");
    }

    return 0;
}

以上为解题
我的思路是使用嵌套循环来进行解答

c语言小白 勿喷