UVa12412

#include <stdio.h>
#include <string.h>
#define maxl 20
#define maxn 10005
#define EPS 1e-5

struct stu{
    char sid[maxl], name[maxl];
    int cid;
    int score[4];
}   stu[maxn];

int n = 0;
int removed[maxn];
int pasn[5];//下标i分别表示通过i科的人数
int pas[4], fai[4], average[4], sum[4];


void add(){
    for(;;){
        printf("Please enter the SID, CID, name and four scores. Enter 0 to finish.\n");
        int sid2 = 1;
        char sid1[maxl];
        scanf("%s", stu[n].sid);
        if( strcmp( stu[n].sid, "0") == 0 )     break;
        scanf("%d %s %d %d %d %d", &stu[n].cid, stu[n].name, &stu[n].score[0], &stu[n].score[1], &stu[n].score[2], &stu[n].score[3]);
        for( int i=0; i<n; i++){
            if( strcmp( stu[n].sid, stu[i].sid) == 0 && !removed[i] ){
                printf("Duplicated SID.\n");
                sid2 = 0;
                break;
            }
        }
        if(sid2)    n++;
    }
}

int rank( float a){
    int r = 1;
    for( int i=0; i<n; i++){
        if( !removed[i] && stu[i].score[0]+stu[i].score[1]+stu[i].score[2]+stu[i].score[3] > a )    r++;
    }

    return r;
}

void DQ( int isq){
    char s[maxl];
    for(;;){
        printf("Please enter SID or name. Enter 0 to finish.\n");
        scanf("%s", s);
        if( strcmp( s, "0") == 0 )  break;
        int r = 0;
        for( int i=0; i<n; i++){
            if( !removed[i] ){
                if( strcmp( stu[i].sid, s) == 0  ||  strcmp( stu[i].name, s) == 0 ){
                    if(isq){
                        printf("%d %s %d %s %d %d %d %d %d %.2f\n", rank(stu[i].score[0]+stu[i].score[1]+stu[i].score[2]+stu[i].score[3]), stu[i].sid, stu[i].cid, stu[i].name, stu[i].score[0], stu[i].score[1], stu[i].score[2], stu[i].score[3], stu[i].score[0]+stu[i].score[1]+stu[i].score[2]+stu[i].score[3], (stu[i].score[0]+stu[i].score[1]+stu[i].score[2]+stu[i].score[3])/4.0+EPS);
                    }else{
                        removed[i] = 1;
                        r++;
                    }
                }
            }
        }
        if(!isq)    printf("%d student(s) removed.\n", r);
    }
}

void cal( int i){
    int idx = 0;
    for( int j=0; j<4; j++){
        if( stu[i].score[j] >= 60 ){
            pas[j]++;
            idx++;
        }else{
            fai[j]++;
        }
        sum[j] += stu[i].score[j];
    }
    for( int j=0; j<5; j++){
        if( idx == j ){
            pasn[j]++;
        }
    }
}

void stat(){
    printf("Please enter class ID, 0 for the whole statistics.\n");
    int c;
    scanf("%d", &c);
    memset( pasn, 0, sizeof(pasn));
    memset( pas, 0, sizeof(pas));
    memset( fai, 0, sizeof(fai));
    memset( average, 0, sizeof(average));
    memset( sum, 0, sizeof(sum));
    int m = 0;
    if(!c){
        for( int i=0; i<n; i++){
            if( !removed[i] )  {cal(i); m++;}
        }
    }else{
        for( int i=0; i<n; i++){
            if( stu[i].cid == c && !removed[i] ){
                cal(i); m++;
            }
        }
    }

    for( int i=0; i<4; i++){
        switch (i)
        {
        case 0: printf("Chinese\n");     break;
        case 1: printf("Mathematics\n"); break;
        case 2: printf("Engilsh\n");     break;
        case 3: printf("Programing\n");  break;
        }
        printf("Average Score:%.2f\nNumber of passed students:%d\nNumber of failed students:%d\n\n", sum[i]*1.0/m+EPS, pas[i], fai[i]);
    }
    printf("Overall:\nNumber of students who passed all subjects: %d\n", pasn[4]);
    printf("Number of students who passed 3 or more subjects: %d\n", pasn[3] + pasn[4]);
    printf("Number of students who passed 2 or more subjects: %d\n", pasn[2] + pasn[3] + pasn[4]);
    printf("Number of students who passed 1 or more subjects: %d\n", pasn[1] + pasn[2] + pasn[3] + pasn[4]);
    printf("Number of students who failed all subjects: %d\n", pasn[0]);
}

int main(){
    memset( removed, 0, sizeof(removed));
    for(;;){
        int choice;
        printf("Welcome to Student Performance Management System (SPMS).\n\n\
1 - Add\n\
2 - Remove\n\
3 - Query\n\
4 - Show ranking\n\
5 - Show Statistics\n\
0 - Exit\n\n");
        scanf("%d", &choice);
        if( choice == 0 )   break;
        if( choice == 1 )   add();
        if( choice == 2 )   DQ(0);
        if( choice == 3 )   DQ(1);
        if( choice == 4 )   printf("Showing the ranklist hurts students' self-esteem. Don't do that.\n");
        if( choice == 5 )   stat();
    }

    return 0;
}