"Learning note", "C language" cyclic structure-while

1. Simple to use

while (condition)
{
Statement 1;
Statement 2;
....
}

If the condition is true, the statement in the loop body is executed (the "loop Body" is the contents of the curly brace {} after the while). Then judge the condition again and repeat the process until the condition is not set to end the while loop

While loop features: If the condition in the while is not in the beginning, then the statement in the loop body will never be executed.

You can omit the curly braces {}, but only the first statement that follows the while is affected. Omitting curly braces is not recommended.

Statement 1;

2. Code

1#include <stdio.h>2 3 /*4 if (condition)5  {6  7  }8  9 While (condition)Ten  { One Loop Body A  } -   - Operating principle the 1. If the initial condition is not established, the loop body will never be executed - 2. If the condition is set up, a loop body is executed, the execution is completed, and the condition is determined again . -   -  Break + directly ends the entire while loop -   + Continue A end the current loop body and go to the next loop body execution at   -  */ -  - intMain () - { -     //1. First identify the actions that need to be performed repeatedly in      -     //2. Re-determination of constraints to      +     //defines the number of times a variable record is made -     intCount =0; the      *     /* $ While (COUNT<50)Panax Notoginseng     { - ++count; the          + if (count%10! = 0) A         { the printf ("Do%d push-ups \ n", count); +         } -     }*/ $      $     /* - While (COUNT<50) -     { the ++count; -         Wuyi if (count%10 = = 0) the         { - //end this cycle directly and enter the next cycle Wu continue; -         } About          $ printf ("Do%d push-ups \ n", count); -     }*/ -      -      while(Count < -) A     { +++count; the          -printf"do the first%d push-ups \ n", count); $          the         if(Count = = -) the         { the              Break; the         } -     } in      the      the     return 0; About}

Practice

1 /*2 prompts the user to enter a positive integer n, computes the 1+2+3+...+n and3  */4 5#include <stdio.h>6 7 intMain ()8 {9     //1. Prompt for inputTenprintf"Please enter a positive integer: \ n"); One      A     //2. Receive input -     //define variables to hold the integer entered by the user -     intN; thescanf"%d", &n); -      -     if(n<=0) -     { +printf"illegal input \ n"); -         return 0; +     } A      at     //3. Calculation -     //(1 + N) * N/2; -     //define variable saving and -     intsum =0; -     intNumber =0;//the default value to be added -      in      while(Number <N) -     { tonumber++; +sum + = number;//Accumulate -     } the      *printf"%d\n", sum); $     Panax Notoginseng     return 0; -}

1 /*2 Title: Calculates the number of multiples of all 3 in a 1~1003 */4 5#include <stdio.h>6 7 intMain ()8 {9     //record the number of multiples of 3Ten     intCount =0; One      A     //record the value of the current check -     intNumber =0; -      the      while(Number < -) -     { -number++; -          +         //Description number is a multiple of 3 -         if(number%3==0) +         { Acount++; at         } -     } -      -printf"number of multiples of 3 in 1~100:%d\n", count); -}

3. Attention Points

1#include <stdio.h>2 3 intMain ()4 {5     /*6 While (Ten)7     {8 printf ("haha \ n");9     }*/Ten      One     /* A int a = ten; - //while (a>0); dead Loop - While (a>0) the     { - a--; - printf ("Hahaha \ n"); -     }*/ +      -     //The simplest cycle of death +     //while (1); A      at     return 0; -}

"Learning note", "C language" cyclic structure-while