例4-4源程序一判断素数Entera number: 9Noint main(void)( inti, m;Entera number: 11printf("Enter a number: ");11 is a prime number!scanf ("%d", &m);for (i = 2; i<= m/2; i++)循环条件？循环的结束条件?if (m % i == 0) break;if (i>m/2&&m!=1)printf("%d is a prime number! In", m);elseprintf("No!\n");1for (i = 2; i <= m/2; i++)if (m % i == 0) printf("No!\n');77else printf("%d is a prime number! In", m);
int main(void) { int i, m; printf(“Enter a number: "); scanf ("%d", &m); for (i = 2; i <= m/2; i++) if (m % i == 0) break; if (i > m/2&&m!=1 ) printf("%d is a prime number! \n", m); else printf("No!\n"); } 例4-4源程序－判断素数 Enter a number: 9 No Enter a number: 11 11 is a prime number! for (i = 2; i <= m/2; i++) if (m % i == 0) printf("No!\n"); else printf("%d is a prime number! \n", m); 循环条件? 循环的结束条件?
for (i = 2; i<=m/2; i++)4.3.2break语句if (m%i==0) breakif (i> m/2) printf("Yes");for(i= 2; i<= m/2; i++)else printf("No!n");if(m%i == 0)(printf("No!n");假break;exp1真语句1printf("Yes");循环体真当循环有多个出口时假expb·表示循环条件语句2·区分结束条件
4.3.2 break 语句 while(exp){ 语句1 if (expb) break; 语句2 } 真 假 exp 语句1 假expb 语 句2 循 环 体 真 for (i = 2; i <= m/2; i++) if (m % i == 0) break; if (i > m/2 ) printf("Yes"); else printf("No!\n"); 当循环有多个出口时： • 表示循环条件 • 区分结束条件 for(i = 2; i <= m/2; i++) if(m%i == 0){ printf("No!\n"); break; } printf("Yes");