switch

/* 表达式和一个整数，或一个字符常量进行比较。表达式必须对整数求值，可以使用字符或整数值。 */ #include<stdio.h> int main() { int num; int indiv,ten,hundred,thousand; int ten_thousand,hundred_thousand,place; printf("请输入一个整数(0~999999)"); scanf("%d",&num); if ( num > 99999 ) place = 6; else if ( num > 9999 ) place = 5; else if ( num > 999 ) place = 4; else if ( num > 99 ) place = 3; else if ( num > 9 ) place = 2; else place = 1; printf ("place = %d\n" , place ); printf ("每位数字为: "); //求出num在各个位上的值 hundred_thousand = num / 100000; ten_thousand = ( num - hundred_thousand*100000) / 10000 ; thousand = ( num - hundred_thousand*10000 - ten_thousand*10000 ) / 1000; hundred = ( num - hundred_thousand*100000 - ten_thousand*10000 - thousand*1000 ) / 100; ten = ( num - hundred_thousand*100000 - ten_thousand*10000 - thousand*1000 - hundred*100 ) / 10; indiv = ( num - hundred_thousand*100000 - ten_thousand*10000 - thousand*1000 - hundred*100 - ten*10 ); //判断num的位数，并根据位数做出输出 switch ( place ) { case 1: printf( "%d", indiv ); printf( "\n反序数字为：" ); printf( "%d\n" ,indiv ); break; case 2: printf( "%d,%d", ten,indiv ); printf( "\n反序数字为：" ); printf( "%d%d\n" ,indiv,ten ); break; case 3: printf( "%d,%d,%d", hundred, ten,indiv ); printf( "\n反序数字为：" ); printf( "%d%%d%d\n" ,indiv,ten ,hundred); break; case 4: printf( "%d,%d,%d,%d",thousand, hundred, ten,indiv ); printf( "\n反序数字为：" ); printf( "%d%%d%d%d\n" ,indiv,ten ,hundred, thousand); break; case 5: printf( "%d,%d,%d,%d,%d", ten_thousand,thousand, hundred, ten,indiv ); printf( "\n反序数字为：" ); printf( "%d%%d%d%d%d\n" ,indiv,ten ,hundred, thousand,ten_thousand); break; case 6: printf( "%d,%d,%d,%d,%d,%d", hundred_thousand, ten_thousand,thousand, hundred, ten,indiv ); printf( "\n反序数字为：" ); printf( "%d%%d%d%d%d%d\n" ,indiv,ten ,hundred, thousand,ten_thousand,hundred_thousand); break; default: printf( "Not find....\n" ); break; } }