39 wiersze
1007 B
C
39 wiersze
1007 B
C
#include "tinyexpr.h"
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#include <stdio.h>
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int main(int argc, char *argv[])
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{
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if (argc < 2) {
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printf("Usage: example2 \"expression\"\n");
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return 0;
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}
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const char *expression = argv[1];
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printf("Evaluating:\n\t%s\n", expression);
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/* This shows an example where the variables
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* x and y are bound at eval-time. */
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double x, y;
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te_variable vars[] = {{"x", &x}, {"y", &y}};
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/* This will compile the expression and check for errors. */
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int err;
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te_expr *n = te_compile(expression, vars, 2, &err);
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if (n) {
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/* The variables can be changed here, and eval can be called as many
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* times as you like. This is fairly efficient because the parsing has
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* already been done. */
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x = 3; y = 4;
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const double r = te_eval(n); printf("Result:\n\t%f\n", r);
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te_free(n);
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} else {
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/* Show the user where the error is at. */
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printf("\t%*s^\nError near here", err-1, "");
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}
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return 0;
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}
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