C/C++練習

1、列印如形：

*
*.*.
*..*..*..
*...*...*...*...
*....*....*....*....*....
*.....*.....*.....*.....*.....*.....
*......*......*......*......*......*......*......
*.......*.......*.......*.......*.......*.......*.......*.......
請按任意鍵繼續. . .

void main()<br />{<br />int i,j,k;<br />int n=8;<br />for (i=1;i<=n;i++)<br />{<br />j=i;<br />for (k=1;k<=j;k++)<br />{<br />cout<<"*";<br />while(j>1)<br />{<br />cout<<".";<br />j--;<br />}<br />j=i;<br />}<br />cout<<endl;<br />}<br />system("pause");<br />}

2、列印如形：

          A
         ABC
        ABCDE
       ABCDEFG
      ABCDEFGHI
     ABCDEFGHIJK
    ABCDEFGHIJKLM
   ABCDEFGHIJKLMNO
  ABCDEFGHIJKLMNOPQ
 ABCDEFGHIJKLMNOPQRS
請按任意鍵繼續. . .

int _tmain(int argc, _TCHAR* argv[])<br />{<br />int i,j,k;<br />char c;<br />for (i=1;i<=10;i++)<br />{<br />c='A';<br />for (j=10-i;j>=0;j--)<br />{<br />printf(" ");<br />}<br />for (k=1;k<=2*i-1;k++)<br />{<br />printf("%c",c);<br />c++;<br />}<br />printf("/n");<br />}<br />system("pause");<br />return 0;<br />}

3、判斷素數

void f(int m)<br />{<br />int i;<br />for (i=2;i<m;i++)<br />{<br />if (m%i==0)<br />{<br />printf("%d不是素數/n",m);<br />return;<br />}<br />}<br />printf("%d是素數/n",m);<br />return;<br />}<br />//i結束的條件也可以是(int)sqrt(m*1.0)。必須乘以1.0