1.求5个同学各个科目的平均分，最高分，最低分
2.题目：Enter a sentence: you can cage a swallow can't you?
    Reversal of sentence: you can't swallow a cage can you?
3.题目：凯撒加密。这里面我的程序里的其他字母都正确，就是不知道为啥，第一个字母“G”本来是变成“J”，却变成了一个汉字。
4.测试是否为同位词（组成单词的字母全部相同）
我输入的不是同位词，可还是显示是同位词。

1.

#include<stdio.h>
 int main(void)
{
    int i,j,a[5][5],b[5],c[5],d[5],e[5],zh,zh1,zd,zx;
    for(i=0;i<5;i++)
    {
        printf("第%d位同学的成绩:",i+1);
        for(j=0;j<5;j++)
        scanf("%d",&a[i][j]);   
    }
    for(j=0;j<5;j++)
    {
        printf("\n第%d位同学的平均分:",j+1);   
        printf("%3d",b[j]);   
    }
        printf("\n每门最高分：");
    for(j=0;j<5;j++)
    {   zd=0;
        for(i=0;i<5;i++)
        {   
            if(a[i][j]>zd)
            zd=a[i][j];
            else
            zd=zd;
        }
        d[j]=zd;
        printf("%3d",d[j]);
    }
    printf("\n每门最低分：");
    for(j=0;j<5;j++)
    {   zx=100;
        for(i=0;i<5;i++)
        {   
            if(a[i][j]<zd)
            zx=a[i][j];
            else
            zx=zx;
        }
        d[j]=zx;
        printf("%3d",e[j]);
    }
}

2.
#include<stdio.h>
int main(void)
{
    printf("Enter a sentence:");
    int i,j=0,k,z;
    char ch,a[50];
    while((ch=getchar())!='\n')
    {
        a[j]=ch;
        j++;
    }
    printf("Reversal of sentence:");
    for(j=j-2,k=0;j>0;j--)
    {
        if(a[j]==32)
        {
            for(i=j+1;k>0;i++,k--)
            printf("%c",a[i]);
        }
        k++;
        i=j;
    }
    for(;k>=0;k--,i++)
    printf("%c",a[i]);
   
 }

3.
#include<stdio.h>
int main(void)
{
    printf("Enter message to be encrypted:");
    int i,j,b;
    char a[80],ch;
    while((ch=getchar())!='\n')
    {
        a[j]=ch;
        j++;
    }
    a[j]='\0';
    printf("Enter shift amount(1-25):");
    scanf("%d",&b);
    for(i=0;i<j;i++)
    {
        if(a[i]>='A'&&a[i]<='Z')
        {
            a[i]=a[i]+b;
            if(a[i]>'Z')
            a[i]=a[i]-26;
        }
        else if(a[i]>='a'&&a[i]<='z')
        {
            a[i]=a[i]+b;
            if(a[i]>'z')
            a[i]=a[i]-26;
        }
        else
        a[i]=a[i];
    }
    printf("Encrypted message:");
    for(i=0;i<j;i++)
    printf("%c",a[i]);
}

4.
#include<stdio.h>
int main(void)
{
    printf("Enter first word:");
    int i=0,j,c[26]={0},d[26]={0},ch1;
    char a[20],b[20],ch;
    while((ch=getchar())!='\n')
    {a[i]=ch;
    i++;}
    printf("Enter second word:");
    while((ch=getchar())!='\n')
    {b[i]=ch;
    i++;}
    for(j=0;j<i;j++)
    {   if(a[i]>='A'&&a[i]<='Z')
        ch1=ch-'A';
        else
        ch1=ch-'a';
        c[ch1]++;}
    for(j=0;j<i;j++)
    {   if(b[i]>='A'&&a[i]<='Z')
        ch1=ch-'A';
        else
        ch1=ch-'a';
        d[ch1]++;}
    for(j=0;j<i;j++)
    {   if(c[j]!=d[j])
        {
            printf("The words are not anagrams.");
            return 0;
        }
      }
      printf("The words are anagrams.");
}