密码学--重合指数计算

密码学--重合指数计算(IC.cpp)如果开发者对于本文件有需要的可以参考，
char word1[26] = { 'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z' };
double p[26];

double math_IC(char* txt) {
int i, j = 0, num = 0;
double IC = 0, frequency[26], p[26];
for (i = 0; i < 26; i ) {
frequency[i] = 0;
}
while (txt[j]) {
if (txt[j] >= 65 && txt[j] <= 90) {
for (i = 0; i < 26; i ) {
if (txt[j] == word1[i])
frequency[i] ;
}
num ;
}
j ;
}
for (i = 0; i < 26; i ) {
p[i] = frequency[i] / num;
IC = p[i] * p[i];
}
return IC;
}
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