关于在C语言中WHILE与IF。。。ELSE的嵌套问题 C语言if和else if，for和while的问题
C\u8bed\u8a00 do while \u548c if... else if... else\u7684\u5d4c\u5957\u51fa\u9519\uff0c\u6025#include#includevoid main() // \u8fd9\u91cc\u6700\u597d\u52a0\u4e0avoid \u8868\u793a\u51fd\u6570\u65e0\u8fd4\u56de\u503c{ float n,x,y; int o,p; o=0;p=0; printf("Enter 7777 to STOP"); do { printf("Enter a number:"); scanf("%f\n",&n); if(n=7777) // \u5224\u65ad\u8bed\u53e5\u5982\u679c\u4e0d\u5199\u201c{}\u201d\u7684\u8bdd\uff0c\u9ed8\u8ba4\u53ea\u5305\u542b\u4e0b\u9762\u7684\u7b2c\u4e00\u884c\uff0c\u6240\u4ee5\u8fd9\u91cc\u6ca1\u9519\uff0c\u4f60\u53ea\u60f3\u6267\u884c\u8fd9\u4e00\u884c printf("Number of items done=%d Negative ite ms=%d",o,p);else if(n>=0) // \u4f46\u662f\u8fd9\u91cc\uff0c\u4f60\u662f\u60f3\u5728n>=0\u7684\u6761\u4ef6\u4e0b\u6267\u884c\u4e0b\u9762\u7684\u4ee3\u7801\u5c31\u9700\u8981\u52a0\u201c{}\u201d{ // \u800c\u4e14if else \u4e4b\u95f4\u662f\u4e0d\u80fd\u52a0\u5176\u4ed6\u7684\u4ee3\u7801\u7684\uff0c\u6240\u4ee5\u9700\u8981\u52a0\u4e0a\u201c{}\u201d x=n*n; printf("Square=%.5f\n",x); y=sqrt(n); printf("root=%.5f\n",y); o=o+1; }else{ printf("Number if negative\n"); x=n*n; printf("square=%.5f\n",x); p=p+1; } }while (n=7777); printf("Number of items done=%d Negative items=%d",o,p);} \u8c22\u8c22
\u4f60\u597d\uff1a
if...else\u4e0eif...else if...else\u76f8\u6bd4\uff0c\u540e\u8005\u5728\u7075\u6d3b\u6027\u548c\u529f\u80fd\u4e0a\u662f\u8981\u5f3a\u5927\u4e00\u4e9b\uff0c\u524d\u8005\u7528\u4e8e\u4e00\u4e2a\u6761\u4ef6\u7684\u4e24\u79cd\u4e0d\u540c\u6267\u884c\u7ed3\u679c\uff0c\u540e\u8005\u5e94\u7528\u4e0e\u591a\u6761\u4ef6\u7684\u5224\u65ad\u548c\u6267\u884c\u7ed3\u679c\uff1b\u4f46\u662f\u4f60\u7528\u591aif\u7ed3\u6784\u3001return\u6765\u7ed3\u675f\u6389\uff0c\u5b9e\u5c5e\u7f16\u7a0b\u964b\u4e60\uff0c\u5982\u679c\u8fd9\u4e2aif\u5728\u4e3b\u51fd\u6570\u91cc\u8fb9\uff0c\u4f7f\u7528return\u7ed3\u675f\u65e0\u7591\u4f1a\u5f15\u8d77\u4e0d\u53ef\u8bbe\u60f3\u7684\u540e\u679c\uff0c\u5efa\u8bae\u76f4\u63a5\u4f7f\u7528if...else if....else\uff0c\u5c31\u7b97\u662f\u4e3a\u4e86\u8fd4\u56de\u67d0\u4e2a\u503c\uff0c\u5728if...else if....else\u7ed3\u6784\u91cc\u4f9d\u7136\u53ef\u4ee5\u4f7f\u7528return\u6765\u8fd4\u56de\u3002
for\u4e0ewhile\uff0cwhile\u662f\u6bd4\u8f83\u5355\u8c03\uff0c\u4f46\u4e0d\u80fd\u5426\u8ba4\u5b83\u81ea\u5df1\u6240\u5177\u6709\u7684\u72ec\u7279\u4f18\u70b9\uff0cfor\u4e0ewhile\u53ef\u4ee5\u76f8\u4e92\u8f6c\u5316\uff0c\u8fd9\u53d6\u51b3\u4e8e\u81ea\u8eab\u7684\u7f16\u7a0b\u7231\u597d\uff0c\u4f46\u662f\u5f53for(\u8868\u8fbe\u5f0f\uff0c\u8868\u8fbe\u5f0f\uff0c\u8868\u8fbe\u5f0f\uff1b\u8868\u8fbe\u5f0f\uff1b\u8868\u8fbe\u5f0f\uff0c\u8868\u8fbe\u5f0f)\u8fd9\u79cd\u7ed3\u6784\u51fa\u73b0\u65f6\uff0c\u8f6c\u4e3awhile\u65e0\u7591\u4f18\u70b9\u7d2f\u8d58\u611f\u3002
\u5e0c\u671b\u6211\u7684\u56de\u7b54\u80fd\u5e2e\u52a9\u5230\u4f60\u3002
while（条件1）
{
if（条件2）
{
表达式1；
}
else
{
表达式2；
}
}
实际上时这样的，条件1为假什么都不执行，条件2为假执行else
绛旓細涓嶅悓鐐瑰氨鏄痠f娌℃湁寰幆鐨勬у瓙锛屼竴鏃︽墽琛岃繃鍚庡氨璺冲嚭璇彞锛岃while鍒ゅ畾涓虹湡鍚庢墽琛屽畠涓嬮潰鐨勮鍙ワ紝鎵ц瀹屽悗杩斿洖鎷彿閲岀户缁垽瀹氾紝鍒ゅ畾涓虹湡缁х画鎵ц璇彞鐭ラ亾鎷彿閲屽垽瀹氫负鍋囦负姝備笁銆佹剰鎬濅笉鍚 while鏄惊鐜鍙ワ紝鍦–璇█涓閫氬父鐢╳hile鏉ヨ〃绀哄惊鐜紝渚嬪鍦╩ain锛堬級鍑芥暟涓竴鑸兘鐢╳hile锛1锛夋潵璁╀富绋嬪簭寰幆鎵ц銆倃hil...
绛旓細鍦–璇█涓閫氬父鐢while鏉ヨ〃绀哄惊鐜紝渚嬪鍦╩ain锛堬級鍑芥暟涓竴鑸兘鐢╳hile锛1锛夋潵璁╀富绋嬪簭寰幆鎵ц銆傚嵆鍦ㄩ昏緫鏉′欢琛ㄨ揪寮忎负鐪熺殑鎯呭喌涓嬶紝while鍙嶅鎵ц寰幆浣撳唴鍖呭惈鐨勮鍙ユ垨璇彞鍧楋紝鐩村埌鏉′欢涓嶆垚绔嬨備緥濡傦細澶╂皵濡傛灉鏄笅闆ㄥ氨鎵ц鐫¤鎸囦护锛岀洿鍒颁笉涓嬮洦涓烘锛涘闃村ぉ銆佹櫞澶╂垨鑰呬笅闆瓑鍏朵粬澶╂皵灏变笉鎵ц鐫¤鎸囦护銆4銆乮f...
绛旓細if,while,do while鐨鍏遍氫箣澶:閮芥湁鏉′欢鍒ゆ柇閮ㄥ垎銆傚尯鍒細if锛氬綋鏉′欢婊¤冻鏃讹紝浼氭墽琛屽悗缁х殑涓涓垨涓缁勮鍙ワ紱褰撴潯浠朵笉婊¤冻鏃讹紝鍓嶉潰鐨勮鍙ュ氨涓嶈鎵ц锛涘綋闇瑕佹椂锛屽彲浠ユ寚瀹氬畠鎵ц鍙︿竴涓垨鍙︿竴缁勮鍙ワ紙else 瀛愬彞锛夈倃hile锛氬綋鏉′欢婊¤冻鏃讹紝浼氶噸澶嶆墽琛屽悗缁х殑涓涓垨涓缁勮鍙ワ紙绉颁负寰幆浣擄級锛涚洿鍒板惊鐜綋涓慨...
绛旓細鍏遍氫箣澶勫湪浜庨兘浼氳繘琛屾潯浠跺垽鏂傚尯鍒涓嬶細if璇彞鏄垽鏂鍙ワ紝鍙墽琛屼竴娆★紝渚嬪 锛歩f(a>0) b=1;褰揳涓烘鏁版椂锛屾墠鎵цb=1;鑻涓嶆槸姝ｆ暟锛岄偅涔坆=1;灏变笉浼氳繍琛屽埌銆備箣鍚巌f璇彞灏辩粨鏉熶簡锛屽彧鍒ゆ柇涓娆>0杩欎釜鏉′欢 while鏄惊鐜鍙ワ紝鍙嶅鎵ц鐩村埌鍏跺惊鐜潯浠朵笉婊¤冻涓烘銆備緥濡傦細while(a>0){ b=b+1;a=...
绛旓細while(){ ...} 濡傛灉while鍚庤竟鎷彿鍐鐨琛ㄨ揪寮忎负鐪燂紝閭ｄ箞鎵ц{}鍐呯殑璇彞锛岀劧鍚庡啀鍒ゆ柇while鍚庤竟锛堬級鐨勮〃杈惧紡鏄惁涓虹湡锛屽鏋滄槸鐪燂紝鍐嶆鎵ц{}鍐呯殑璇彞锛岀洿鍒帮紙锛夊唴鐨勬潯浠朵负鍋囥俰f(){ ...} 璇彞A ...濡傛灉if鍚庤竟锛堬級鍐呬负鐪燂紝鎵ц{}鍐呰鍙ワ紝鎵ц瀹屼箣鍚庢墽琛屼笅杈硅鍙銆傚鏋滀负鍋囩洿鎺ユ墽琛岃鍙 for(...
绛旓細while(a) 琛ㄧず褰揳!=0鏃舵墽琛屽惊鐜紝鍏剁瓑浠蜂簬while(a!=0)銆俰f(a) 鍚屼笂銆倃hile(!a) 琛ㄧず褰揳=0鏃舵墽琛屽惊鐜紝鍏剁瓑浠蜂簬while(a==0)銆俰f(!a) 鍚屼笂銆俰f(j%2)continue; 琛ㄧずj%2!=0鏃舵墽琛宑ontinue;j%2!=0琛ㄧずj闄や互2鐨浣欐暟涓嶄负闆讹紝鍗抽櫎涓嶅敖銆傚嵆j涓哄鏁版椂鎵цcontinue;...
绛旓細if鏄垽鏂紝while鏄惊鐜傜涓涓鐨刬f锛屽彧鎵ц涓娆″悗缁х画澶栭潰for寰幆銆傜浜屼釜while鏄牴鎹垽鏂潯浠跺喅瀹氭槸鍚﹀惊鐜紝涓鏃﹁繘鍏ヤ簡while寰幆鍚庣敱浜巌鍜宮鐨勫间笉鑳芥敼鍙橈紝鎵浠ュ垽鏂粨鏋滀竴鐩翠负鐪燂紝鍦ㄥ惊鐜閲鍑轰笉鏉ワ紝鍗虫寰幆銆
绛旓細while 鍜 if 鎷彿涓殑閮芥槸鍒ゆ柇鏉′欢 鍒嗕负鐪熷拰鍋囷紝濡傛灉鏄湡 灏辨墽琛屼粬浠殑绋嬪簭锛屼竴鑸鍦╟璇█涓 鍋囩敤0琛ㄧず 鍏朵粬鏁拌〃绀虹湡 鎵浠 濡傛灉num涓嶄负0 灏辫〃绀虹湡 鎵ц璇ヨ鍙ョ殑鍐呭锛屼负0琛ㄧず 鍋 璺宠繃璇ヨ鍙ュ唴瀹
绛旓細涓嶅彲浠...while鏄惊鐜鍙,婊¤冻鏉′欢鍒欑户缁惊鐜痠f鍙槸鍒ゆ柇璇彞,鍖呮嫭鐨璇彞鍙墽琛屼竴娆
绛旓細绠鍗鐨璇磇f浠庝笂鍒颁笅鍙墽琛屼竴娆★紝while鍙鏉′欢婊¤冻鏃犻檺寰幆锛宖or涓鑸瀹氬惊鐜鏁版椂鐢紝浣犲彲浠ユ壘涓畝鍗曠殑璇彞鎶奿f鎹㈡垚while锛屾垨鑰呮妸while鎹㈡垚if锛屼竴鐪煎氨鑳界湅鍑哄尯鍒紝鏅氬惊鐜彲鑳藉彉鎴愭棤闄愬惊鐜
