第 6 章 C控制语句：循环

小程序：扫一扫查出行
【扫一扫了解最新限行尾号】
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6.16.3 使用嵌套循环，按下面格式打印字母：

FED

FEDC

FEDCB

FEDCBA

#include <stdio.h> int main()
{
const int ROWS = ; for (int row(); row != ROWS; ++row)
{
for (char ch('F'); ch >= 'F' - row; --ch)
printf("%c",ch); printf("\n");
} return ;
}

6.16.3

6.16.4 使用嵌套循环，按下面格式打印字母：

DEF

GHIJ

KLMNO

PQRSTU

#include <stdio.h> int main()
{
const int ROWS = ;
const int COLS = ;
char ch = 'A'; for (int row(); row != ROWS; ++row)
{
for (int col(); col <= row; ++col, ++ch)
printf("%c", ch); printf("\n");
} return ;
}

6.16.4

6.16.5

#include <stdio.h> int main()
{
printf("Input a letter: "); char ch;
while ( == scanf("%c", &ch))
{
if ('\n' == ch || ' ' == ch || '\t' == ch)
continue; if (ch < 'A' || ch > 'z')
printf("\nIt's not a letter, try again: ");
else
break;
} if (ch >= 'a') ch -= 'a' - 'A'; const int ROWS = ch - 'A' + ;
const char *SPACE = " "; for (int row(); row != ROWS; ++row)
{
for (int col(); col != ROWS - row; ++col)
printf(SPACE); char chTmp = 'A';
for (; chTmp != 'A' + row; ++chTmp)
printf("%c", chTmp); for (; chTmp != 'A' - ; --chTmp)
printf("%c", chTmp); printf("\n");
} return ;
}