The following program works when valid input is entered. When invalid input is entered it goes into a loop and stops working. I have included the code along with how I want the code to behave when invalid input is entered.
Code:#include<stdio.h> #include<stdlib.h> #include<time.h> #define MAX_QUERIES 12 #define N_DIGITS 4 int isValid(int N){ //Create an array each index represent a digit int digit[10]={0}; int lastDigit = 0; //If Number is 4 digit int lower = 1; int upper = 9; int x = 0; for(;x<(N_DIGITS-1);x++){ upper=upper*10+9; lower=lower*10; } if(N>=lower && N<upper){ //Iterate through each digit in N while(N>0){ lastDigit = N%10; //if digit is 0 then N is not valid if(lastDigit==0) return 0; //if this digit is already seen then that means digit is repeated if(digit[lastDigit]==1) return 0; //if not seen earlier then mark it as seen digit[lastDigit]=1; N=N/10; } return 1; } else return 0; } //Choose a 4 digit valid number int choose_N(){ int N=0; while(1){ N = rand(); if(isValid(N)) return N; } return -1; } int matches(int N,int M){ int dN=0; int dM=0; int m=0; while(N>0 && M>0){ dN=N%10; dM=M%10; //if both the last digit of N and M are same them increment the count of match if(dN==dM) m++; N=N/10; M=M/10; } return m; } int hits(int N,int M){ //Array to track what all digits are there in N int digitsN[10]={0}; int lastDigit = 0; int i=1; int hit=0; while(N>0){ lastDigit=N%10; //index at lastDigit in digitsN is seen so adding the index from right side e.g 4920 has index as 4321 digitsN[lastDigit]=i++; N=N/10; } i=1; while(M>0){ lastDigit=M%10; //Check if last digit of M is somewhere in the N but not at the same index if(digitsN[lastDigit]!=0 && digitsN[lastDigit]!=i) hit++; M=M/10; i++; } return hit; } int main(){ srand(time(0)); int N = choose_N(); //printf("Number guessed = %d\n",N); printf("***Welcome to the MATCH and HIT game***\n"); printf("The computer has selected a 4-digit number.\n"); printf("Try to deduce it in 12 rounds of queries.\n"); int round=1; int M=0; int numOfInputRead=0; while(round<=MAX_QUERIES){ printf("\nRound #%d\n",round); while(numOfInputRead==0){ fflush(stdin); printf("Please enter your query (4 digits):"); numOfInputRead = scanf("%d",&M); if(numOfInputRead==1 && isValid(M)==1) break; else{ printf("Invalid number. Please try again!\n"); numOfInputRead=0; } } numOfInputRead=0; int m = matches(N,M); int h = hits(N,M); printf("\n-> %d match and %d hits ",m,h); if(m==N_DIGITS){ printf("\n**********************************\n"); printf("CONGRATULATIONS! You won the game!\n"); printf("**********************************\n"); return 0; } round++; } printf("\n**********************************\n"); printf("Sorry, out of queries. Game over!\n"); printf("**********************************\n"); return 0; }
