第7章字符串課后習(xí)題答案一、單選題1.B2.D3.C4.D5.C6.D7.D8.A9.B10.C二、程序填空題1.(str1[i]!='\0')str2[i]=str1[i];str2[i]='\0';2.i=0s1[i]!='\0's1[i]=s2[j]j++s1[i]='\0'3.mystrcmp(str1,str2)(*s1==*s2)return*s1-*s2;4.gets(cstr)ls*10+cstr[ii]-'0'5.p=s;*p!=0;p++*p==a*p=b三、編程題1.#include<stdio.h>voidfind(char*p);intmain(){//數(shù)字一個字符串charstr[80];gets_s(str);//調(diào)用函數(shù)find(str);}voidfind(char*p){inti,num[10]={0},j=0,m=0;intflag=0;for(i=0;*(p+i)!='\0';i++){if(*(p+i)>='0'&&*(p+i)<='9'){m=m*10+(*(p+i)-'0');flag=1;}else{if(flag==1){num[j++]=m;m=0;}flag=0;}}if(flag==1){num[j++]=m;}num[j]='\0';for(i=0;num[i]!='\0';i++){printf("%d\t",num[i]);}}2.#include<stdio.h>intmain(){//1.輸入一串字符串charstr[100];inti,count=0,sum=0;gets(str);for(i=0;str[i]!='\0';i++){//2.提取其中數(shù)字//2.1組合數(shù)字[無法完成]-換個思路，去掉所有的非數(shù)字元素//2.1.1一個組合前后都是字母，遇見字母組合停止記錄if(str[i]>='0'&&str[i]<='9'){count=count*10+(str[i]-'0');//3.1數(shù)字的和是后面數(shù)字和10倍相加，相當(dāng)與記錄}else{sum=sum+count;//3.2如果遇見字母就停止記錄，做相加count=0;}//3.數(shù)字相加}printf("%d\n",sum);return0;}3.#include<stdio.h>chara[101];inti=0;intmain(){gets(a);while(a[i]!=NULL){if((a[i]>=97)&&(a[i]<=122))a[i]=a[i]-32;i++;}puts(a);return0;}4.#include<stdio.h>intMyStrlen(charstr[]);intMyStrlen(charstr[]){ inti;intlen=0;for(i=0;str[i]!='\0';i++）{ len++;}return(len);} intmain(){ chara[80];intlen;printf("Pleaseenterastring:");gets(a);len=MyStrlen(a);printf("Thelengthofthestringis:%d\n",len);return0;}5.#include<stdio.h>#include<string.h>intmain(){chara[81];gets(a);intl=strlen(a);charm=a[0];for(inti=0;i<l;i++){if(m<a[i])m=a[i];}printf("%c",m);return0;}6.#include<stdio.h>#include<string.h>#defineN100intmain(){chara[N];intlen,i;printf("請輸入一個字符串：");gets(a);len=strlen(a);printf("逆序輸出結(jié)果為：");for(i=len-1;i>=0;i--)printf("%c",a[i]);printf("\n");return0;}7.#include<stdio.h>#include<math.h>intmain(){charstr[33];inti,t=7,sum=0;intcnt=32;gets(str);//回車鍵占據(jù)一個空格,數(shù)組長度應(yīng)為33，小了會導(dǎo)致數(shù)組越界訪問for(i=0;i<32;i++){str[i]=str[i]-48;//將字符轉(zhuǎn)為數(shù)字sum=sum+str[i]*pow(2,t);if(t==0){printf("%d",sum);t=7;//計算完一組數(shù)，將sum清零