4.循环语句

循环可以用while,do,for,goto语句表述

while (condition) statement;

do statement while(condition);

for (for-init-statement; condition; expression) statement;

goto identifier;

identifier: statement;

while语句代码段

int a = 0;while( a > 0 ){    a--;}

do语句代码段

int a = 0;do {    a--;}while( a > 0 );

for语句代码段

int sum = 0;int i;

for( i=1; i <= 100;i++){    sum += i;}

goto语句

int i, j;

for ( i = 0; i < 10; i++ ){    printf( "Outer loop executing. i = %d\n", i );    for ( j = 0; j < 2; j++ )    {        printf( " Inner loop executing. j = %d\n", j );        if ( i == 3 )            goto stop;    }}

// This message does not print: printf( "Loop exited. i = %d\n", i );

stop: printf( "Jumped to stop. i = %d\n", i );