D編程語(yǔ)言允許使用一個(gè)循環(huán)里嵌套另一個(gè)循環(huán)。以下部分顯示幾個(gè)例子來(lái)說(shuō)明這一概念。
語(yǔ)法嵌套在D環(huán)語(yǔ)句如下：
for ( init; condition; increment ) { for ( init; condition; increment ) { statement(s); } statement(s); }
在D編程語(yǔ)言while循環(huán)語(yǔ)句語(yǔ)法嵌套如下：
while(condition) { while(condition) { statement(s); } statement(s); }
嵌套do...while的語(yǔ)法在D編程語(yǔ)言循環(huán)語(yǔ)句如下：
do { statement(s); do { statement(s); }while( condition ); }while( condition );
在循環(huán)嵌套最后需要說(shuō)明的是，可以把任何類(lèi)型的循環(huán)的任何其他類(lèi)型的循環(huán)里面。例如，一個(gè)for循環(huán)可以放在一個(gè)while循環(huán)中，反之亦然。
下面的程序使用一個(gè)嵌套的for循環(huán)來(lái)找出2-100的素?cái)?shù)：
import std.stdio; int main () { /* local variable definition */ int i, j; for(i=2; i<100; i++) { for(j=2; j <= (i/j); j++) if(!(i%j)) break; // if factor found, not prime if(j > (i/j)) writefln("%d is prime", i); } return 0; }
當(dāng)上面的代碼被編譯并執(zhí)行，它會(huì)產(chǎn)生以下結(jié)果：
2 is prime 3 is prime 5 is prime 7 is prime 11 is prime 13 is prime 17 is prime 19 is prime 23 is prime 29 is prime 31 is prime 37 is prime 41 is prime 43 is prime 47 is prime 53 is prime 59 is prime 61 is prime 67 is prime 71 is prime 73 is prime 79 is prime 83 is prime 89 is prime 97 is prime
掃碼關(guān)注鍍金池微信號(hào)
手機(jī)訂課，優(yōu)惠多多
